How to replace your sprag clutch.

[odie_trackie]

I just replaced my sprag clutch this weekend. After reading numerous posts on the forum, I was prepared to see a mush of oil, ground up metal parts when I pulled off the my alternator cover. Fortunately, my clutch failed in a "safe" manner. Meaning the only parts damaged was the actual sprag clutch and the bearing housing. Total cost outside of tools: $315.
I used the Aprilia sprag clutch housing and the Ducati sprag clutch.

Since there seems to be a lot of people who have done this repair and said "it's not that hard" but don't post pics, I thought I would try and reverse that trend.

Here's my write up of the repair...with pics.

Aprilia Sprag Clutch Fix
Materials/tools required
14mm hex key
2-3ft breaker bar or lever arm for a 1/2 drive ratchet
Various smaller Allen keys (4,5,6).
small hose clamps
Oil 5w50 or 10w50
Oil filter (if it hasn't been changed in a while
new alternator cover gasket, PN AP0650340
plumbers torch
Aprilia flywheel puller
27mm socket.
snap ring pliers.
Verinier or digital calipers.
Sprag clutch (Ducati equivalent: PN 70140071A about $170 via local Ducati dealer).
Sprag clutch bearing housing
Locktite 648 (green).
Locktite 243 if you remove the alternator from the cover.
Aprilia V990 engine manual (only $8 download from AF1).
Lots of clean rags.

Disclaimer: this is just a guide and I do not claim that it's all comprehensive. Get the manual and follow the directions regarding torque and use of locktite. Do not even think about starting this job without both the bike shop manual AND the V990 shop manual. If you haven't done something like shimmed your values, just take it to the dealer. It took me about 2-3 hours which means, a good Aprilia tech should only take 1.5-2.



1) Drain the oil.
1.1) Check for metal particles in the oil.
2) Remove the oil reservoir
3) Remove the clutch slave cylinder
4) Disconnect the alternator connector
4) Remove the Alternator cover.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08-025.jpg

If you can't disconnect the alternator, unbolt it from the cover and hang it on your frame slider.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_023.jpg

DO NOT UNDER ANY CIRCUMSTANCES USE THE STARTER!!!! YOU WILL CAUSE MAJOR DAMAGE TO YOUR ENGINE!!!!!

5) Check the Sprag clutch operation.
5.1) Pull out the intermediate starter drive gear.
5.2) Try to turn the sprag drive gear. It should turn smoothly in one direction only. This by no means that the sprag clutch is good.
6) Check the condition of the gears between the starter and the sprag gear.
6.1) The gears take a huge beating if the sprag clutch is failing or if someone tried to start it with the cover off.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_019.jpg

7) Check the condition of the gear shaft bosses on the alternator/starter cover.
8) Insert the Aprilia Crank Holding tool on the right side of the bike.
8.1) turn the crank till either the front or rear cylinder is at TDC.
8.2) screw in the tool (an M8 wing nut bolt)till it stops.
8.3) Move the crank back and forth a little till you feel the notch in the crank.
8.4) You should be able to screw in the bolt for 2-3 more turns. This will hold your crank still while you remove and replace the main M16 bolt holding on your flywheel.
9) Remove the M16 bolt holding on the flywheel
10) Loosen the bolts holding on the sprag bearing housing.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_022.jpg

11) Use the plumber's torch to heat up the center of the flywheel with the bolt removed (it took me about 1-2 minutes, till it just started to turn a little brown).
12) Quickly screw in the puller and use the long breaker bar (2-3ft) to apply a medium amount of torque.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_001.jpg
http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_002.jpg

NOTE: it didn't take too much torque to get it off. Be careful not to strip the threads in the flywheel.
WARNING: The flywheel will be VERY HOT!!!! Handle with care.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_004.jpg
http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_005.jpg

I let it cool for a while before disassembling the flywheel and sprag clutch.

13) Remove the sprag bearing housing from the flywheel.
14) Remove the sprag clutch from the sprag bearing housing. PAY ATTENTION TO WHICH WAY THE FLANGE IS ORIENTED!


15) remove the sprag drive gear.
16) Check the condition of the inner bearing surface (brass with dimples).
16.1) The shop manual said 1.382 was the wear limit, my is at 1.378.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_006.jpg

Your can sort of make out the reading on the caliper.
17) Check the condition of the sprag clutch (outer) surface.
17.1) should be smooth with not pits or signs of galling.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_003.jpg

18) Check the condition of the sprag clutch.
18.1) All the engagement pieces should be polished and smooth. Again, my was smooth but I replaced it anyway.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_010.jpg

19.2) The spring holding the whole thing together should be tight. Mine was quite loose.
19) Check the condition of the sprag bearing housing inner surface.
19.1) The inner surface shoul be smooth with no gouges, pits or excessive wear. This is the part that was obviously bad on my bike. You can see the gouges worn into the surface.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_007.jpg
http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_009.jpg
http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_008.jpg

20) Replace the sprag clutch parts as necessary.
20.1) The flange side of the sprag clutch goes against the flywheel.

http://www.odiesystems.com/photos/Moto_Pics/Aprilia_Sprag_Fix/Pics_07-08-08_013.jpg

20.2) Use the snap ring pliers to squeeze the snap ring to insert the sprag clutch into the bearing housing.
20.2) Attach the bearing housing and sprag clutch to the flywheel. Follow the shop manual to apply the locktite between the bearing housing and the flywheel and on the bolts.
20.3) Apply locktite 648(green) to the crankshaft taper.
20.3) Getting the flywheel/sprag clutch on the sprag drive gear was a little tricky. You have to turn the flywheel in the freewheeling direction and kind of wiggle it to get it on.
21) Torque the M16 bolt down to 94ft-lbs.
22) Stop and check that all bolts are tight.
23) Remove the Aprilia Crank Holding tool.
24) Make sure the sprag clutch works correctly: slips smoothly in one direction only.
25) Remove and replace the oil filter at this point if you chose to do so.
26) Using a new gasket, fit the alternator cover.
27) Attach the clutch slave cylinder.
27) Refill the oil and Check all fasteners are tight.
I didn't take any more pics because I was too nervous at this point.

28) Make sure the Aprilia Crank holding tool has been removed!
29) Take a deep breath!
30) Say a prayer to the Motorcycle maintenance gods.
31) Fire it up and get the oil pressure up.
32) Get it warmed up and then check for leaks.

[Diablo1]

Thanks for the excellent job. I noticed your stator looks good - no sign of heat discoloring the insulation on the wires. It seems every time someone shows us a stator, it's toasted. You mind telling us the history of your bike? Year, mileage, original stator or replacement?

[odie_trackie]

Thanks for the kudos.

To be honest, the history on this is a little fuzzy. I've been digging into the bike to evaluate it's state of care.

It seems like the previous owner *used* to take care of it, but it looks like it got neglected as of late.
He said he did the 13k service last year.

It's a 2001 RSVR with 18,000miles, Akrapovic exhaust, and the two up seating subframe retro fit.

The oil looked pretty clean and the inside was pretty clean.

What causes the alternator stator to overheat?

[odie_trackie]

Oh, I don't know if the stator is original or not. Sorry.

[ChrisRam]

Very Good Write up, it should be a sticky or at least be linked to in a sticky that covers stuff like this.

[Diablo1]

What causes the alternator stator to overheat?

It's a permanent magnet alternator with a shunt regulator. Current in the stator windings increases with rpm, and so does heat. I don't know if they produced some dodgy stators with marginal insulation on the wires or the diameter of the wire is too small, but some on the forum have been stricken with suddenly smoked stators.

[ghostrider71]

This is a great write-up and I definitely will NOT be doing this MYSELF!! :bond:

Thanks for helping me decide to not butcher my engine on my own...priceless! :happy:

This MUST be stickied...! :plus:

gr

[Janky]

:cheers:A lot of people will benefit from your picturesque threads,keep up the good work.:burnout:

[soofle616]

:plus: my "spare" engine will eventually be getting torn into because of a bad sprag. it would be nice to have this stickied so I don't lose it between now and then.

[odie_trackie]

Thank you everyone! I really appreciate it. Ok, so who makes threads sticky?

[Janky]

Sprag clutch (Ducati equivalent: PN 70140071A about $170

:cheers:I am very glad that i could help all

[Sal Khan]

One of the best write-ups I've seen!

And now I'm REALLY hoping that never happens to mine! :D

[ARAIHEAD]

Excellent write up, if ever mine gans, i'll get grahamcoxon to fix it cos he's a bit of a whizz-kid at stuff like that, hell he even managed to change his risers.......EVENTUALLY!!:eek::bump:

[odie_trackie]

Oh, that's right. We have to give credit where credit is due! Thanks for figuring out the Ducati equivalent. That saved me a good $150!!!!



Sprag clutch (Ducati equivalent: PN 70140071A about $170

:cheers:I am very glad that i could help all

[Janky]

Oh, that's right. We have to give credit where credit is due! Thanks for figuring out the Ducati equivalent. That saved me a good $150!!!!

:cheers:One for all,all for one!!:worship:

[Beau1K]

STICKIE?? Looks like a good one for it...or link in tech tips to this thread?

[Micah / AF1 Racing]

It is almost like big brother is watching huh? Great pics, great read and you are spot on in terms of valid data.

[NorCalRSV]

Well explained...I should have read this before. I just completed mine...and found that the sprag housing was worn. Great job for future reference though

[odie_trackie]

Thanks guys! I'm glad I could be of service and I'm glad it's a sticky now.

Save some poor blokes the trouble.

[Janky]

It is almost like big brother is watching huh? Great pics, great read and you are spot on in terms of valid data.:cheers::banana:

[Brucetafer]

has anybody had one of these done by a Shop? how much it costs?? im scared as shit to think this is going to happen to my bike... whats the chances of it happening?? anyway to postpone the breakage?

[odie_trackie]

I asked the local shop down here in SD. They had a Falco with a seized sprag. They charged the guys 4hours of labor at ~$80/hr.

Yeah...ouch!


has anybody had one of these done by a Shop? how much it costs?? im scared as shit to think this is going to happen to my bike... whats the chances of it happening?? anyway to postpone the breakage?

[odie_trackie]

Oh, I didn't see the other questions.

What year bike do you have? How many miles? Does it start easily now?
The best way to keep your sprag alive and kicking is to make sure the charging/starting electrical is in tip-top shape. That means a strong battery and make sure the infamous brown connector is in good shape and your solenoid is working well.

The biggest reason for these to fail is a weak starting system. The stock battery (at least on the 98-03) was a little weak for the bike. Get the upgraded battery (so a search for "sprag", there are tons of threads on this), keep the bike on a trickle charger if you don't ride a lot and that will take care of most of your issues.


has anybody had one of these done by a Shop? how much it costs?? im scared as shit to think this is going to happen to my bike... whats the chances of it happening?? anyway to postpone the breakage?

[Brucetafer]

ooo, sounds great.. i have a huge battery in my bike, and its on a trickle charger... so i should be good, its a 02 R, 13k Miles... all my wiring looks good,

[odie_trackie]

Sounds like you are in good shape. If it starts right up with no muss and no fuss, you should be good to go.

[Janky]

:cheers:It helps to shut of your bike while in first then in to neutral,then you dont hawe the kick back which helps the life of the sprag:banana:

[Jack_Attack]

:plus: my "spare" engine will eventually be getting torn into because of a bad sprag. it would be nice to have this stickied so I don't lose it between now and then.


You can just copy the article and paste it in "Word" format. Print it out on a color printer and save it on a drive.

[adam567265]

I posted pics of my sprag when it went on a different thread but i thought id add them here with the cost of new parts...

Sprag clutch 174.92 british pounds
Sprag housing 58.98
Sprag gear 136.29
Idle gear 41.21
Double gear 92.28
Pins 3.09 each

and it can ruin your starter 364.87 ouch !

luckily i found a second hand starter and took a risk i got it for 70 pound plus 10 postage. and i got a Spag clutch, housing and all gears and pins for 150 quid .. i was lucky it came up at the right time, as there normaly sold in with complete engines.

To be honest i fitted mine myself, but i got a quote from an aprilia dealership and they wanted 2 hours labour, i did it in less but you know dealerships. so about 40 quid an hour.

If you want to know if your sprag is on the way out, every now and then youll get a horrible kickback after shutting down, and sometimes when starting your motor will just spin and not pick up the crank .. this is a good sign the spring is on the way out .. unfortunately its not avaliable seperately ! .. these intermittent problems will continue until it wont start all together, it can also cause starter damage if it breaks up and locks the starting gears ...... PICS !

[adam567265]

:cheers:It helps to shut of your bike while in first then in to neutral,then you dont hawe the kick back which helps the life of the sprag:banana:


its also easier to find neutral like this aswell .... am i the only person who finds it a bitch !

[Janky]

:cheers:The check of the sprag,starts perfect,no issues but want to see 03 R Finale Edizione Evo:burnout:, 33000km,pull down,want to see,1 -st!:)

[losthaga]

Bruce, I had mine done at Martin's Eurosports in Coopersburg PA 18036. (610)282-9300. My bike had 11303 miles on it when my sprag failed. No warning just wouldn't start one day. They didn't break down the parts price. Receipt reads like this. 1 Starter sprag assy. $597.58 1oil filter $11.33, Diagnoise sprag $17.25, R&R Sprag/Oil $241.50 Parts sub total: $608.91 Labor sub total $258.75 I used all Aprilia OEM parts in mine. I replaced the entire thing, just to be safe! They all seem to fail with time. Start the bike as least time as you can and always keep a STRONG BATTERY in her. I use a dry cell battery now and a Yamaha relay. Trickle charger is a big plus. If the bike don't start right easy, stop trying and charge the battery!
has anybody had one of these done by a Shop? how much it costs?? im scared as shit to think this is going to happen to my bike... whats the chances of it happening?? anyway to postpone the breakage?

[Hatchman]

I would say prevention would be:
Bigger battery on trickle charge
Yamaha Starter Relay
Brown connector 'mod' (soldered connections and bigger wire to battery)
European headlight switch so you can turn all lights off while starting

Great writeup, hope I never have to use it. :)

[odie_trackie]

Those are all good points. I like the Euro light switch idea.
Something else I did recently was to replace the turn signals, running lights and brakes lights to LEDs. I noticed that the instrument back lighting would dim every time I would hit the brakes. That means it's drawing non-trivial amount of current. After I switched, the gauge lights don't dim.
I got a LED timer relay too.

I might get some LED gauge backlights too and maybe a HID kit for the main headlight.


Thanks for the kudos. I'm glad it's been useful.




I would say prevention would be:
Bigger battery on trickle charge
Yamaha Starter Relay
Brown connector 'mod' (soldered connections and bigger wire to battery)
European headlight switch so you can turn all lights off while starting

Great writeup, hope I never have to use it. :)

[Futura]

How does a sprag failure (in the stator housing?) damage the starter?

[kzmille]

It appears from the pictures above that the sprag might have locked up completely which then spun the starter at high speed. But I wasn't there, so...

[Ally V60]

has anybody had one of these done by a Shop? how much it costs?? im scared as shit to think this is going to happen to my bike... whats the chances of it happening?? anyway to postpone the breakage?

Mine was kind of fooked/knackered/toast! all in a oner, cost the wrong side of €750, 2 years ago. At todays rate it would be cheaper to by a second engine!

[Phydeaux]

http://www.apriliaforum.com/forums/showthread.php?t=166304

1000 miles as of today.

[ZdaMan]

Well I got mine done. Ducati sprag and oem housing. Wasn't as bad as I thought it would be. However, I did end up with a problem that took more time to diagnose and fix then the sprag. A wire got pulled out the
Crankshaft position sensor. Must of barely been making contact because no codes showed up.

So my advice to the next guy is to use caution when you open the case. There isnt much slack on the wires

[mille03]

this is gold . it's good to see people helping other people . thanks

[odie_trackie]

Well, I am really pleased that this is helping people out. That was my original intent.

[ZdaMan]

The more I think about it I believe the wire from the crankshaft position sensor was loose the whole time and this is why the sprag went bad. That and i am a idiot because I didnt know when to stop trying to crank it:bond: Was more worried about meeting my buddies and missing the ride then anything.

[odie_trackie]

Well, it's not the really the cranking itself that kills the sprag. It's the engine kicking back that whacks it.
If the engine is hard to start, invariably you will get more "kickbacks" and that will hasten the sprags doom.

But you may have a point. That wire being loose and providing an iffy connection probably contributed to your spags departure from this world.

[adelyser]

I just did my sprag a few weeks ago. Big thanks to all on this thread. I went with the OEM housing, and a BMW sprag, works like brand new.

After comparing the worn vs. new parts, I feel that the sprag was probably ok, it was the housing that was worn out, definite grooves worn into it.

My biggest pain was getting the stubborn flywheel off. I bought the 22mm bolt, and tried pulling it off after heating it, all I did was mangle the threads. I used my oxy-acetylene torch, and started heating it just til it started turning color, and it fell off on it's own.

Bike runs awesome now.

[odie_trackie]

Very glad this thread has been able to ease someone through what seems to be the RSV1000R right of passage.

Maybe we should say:
"There are only two kinds of Mille owners: those who have had a failed sprag and those who are about to."



I just did my sprag a few weeks ago. Big thanks to all on this thread. I went with the OEM housing, and a BMW sprag, works like brand new.

After comparing the worn vs. new parts, I feel that the sprag was probably ok, it was the housing that was worn out, definite grooves worn into it.

My biggest pain was getting the stubborn flywheel off. I bought the 22mm bolt, and tried pulling it off after heating it, all I did was mangle the threads. I used my oxy-acetylene torch, and started heating it just til it started turning color, and it fell off on it's own.

Bike runs awesome now.

[SmaRTrxxv]

I just did my sprag a few weeks ago. Big thanks to all on this thread. I went with the OEM housing, and a BMW sprag, works like brand new.

Second that

I also went with the BMW sprag, I works perfectly :-)

Thore

[odie_trackie]

Ok, I noticed that my pictures weren't showing up. I fixed it now so folks can see what I am talking about.

Happy sprag fixing!

[stupeo]

I just replaced my sprag, and this guide was a GREAT help :)
although there were a couple of points that i did not follow..
1st what's the 27mm socket for ? i had no need for it all.
2nd There is no need to remove the slave cylinder ?

My bike it appears has had a whole bunch of cowboys working on it in the past, The alternator cover gasket was missing and looked like they had used clear silicone bathroom sealant instead !! the flywheel looks as if someone had chewed it with a bar or screwdriver, Probably a trying to remove it without a puller for a previous sprag replacement ?
Couple of bolts with stripped thread, oil feed pipes completely wrecked etc etc etc

The Aprilia crank holding tool, bought from an Aprilia Main dealer was wrong !! :WTF: Luckily i found a suitable bolt in the shed ..
The Flywheel puller turned out to be wrong, But i still managed to succeed using it. the trick i found after speaking to a mechanic friend is to make sure the flywheel is HOT.... not warm but bloody hot, that way the loctite breaks down.. once heated up to a high enough temp, the flywheel was REALLY EASY to pop off :)

But anyway other than this the process went quite smoothly, The BMW sprag spins the opposite way to the Aprilia sprag, I had read that it can just be put in back to front, Or you can gently move the spring aside and turn the lobes, I opted to turn the lobes as it only took five mins and i just felt it was better than putting it in back to front ?
Also i had spoken to an Aprilia mechanic about replacing the housing if it was scored, And he told me that he has replaced 100's of sprags and never needed to replaced the housing !! Don't know if he's right or wrong, But i followed his advice and used the orginal housing which WAS scored but not really that heavy.

So far so good, The bike started on the button first time, No crunching horrible noises :burnout:

Total time to do job was about 3 hrs, but we did have problems caused by the previous cowboy mechanic !! and i'm certain i could probably do it in half the time with the right tools and not having to fix someone else's errors ?
My skill level is not too high although i'm always willing to try..

Basically i think any competant home mechanic can do this job with not too much difficulty.
Total cost in UK £s
BMW sprag £62 delivered (compared to £195 from Aprilia)
Flywheel puller £14
engine lock bolt £5
Loctite 648 £7
Gasket £8
New oil and filter £50

[odie_trackie]

If I remember correctly, the 27mm socket was for the flywheel puller I got.

Not sure exactly why I pulled the clutch slave, but I would guess at the time I couldn't see a way forward without detaching the cylinder.


I just replaced my sprag, and this guide was a GREAT help
although there were a couple of points that i did not follow..
1st what's the 27mm socket for ? i had no need for it all.
2nd There is no need to remove the slave cylinder ?

[Inunf]

Does anyone have the part# for the BMW sprag?

[adelyser]

12112343296 is the BMW part number that I ordered.

[Inunf]

Cheers!

[indyjoe]

It helps to shut of your bike while in first then in to neutral,then you dont hawe the kick back which helps the life of the sprag
its also easier to find neutral like this aswell .... am i the only person who finds it a bitch !

Dumb Question, do you mean I should be shutting down the bike in nuetral. I always try to start it in nuetral. Is this better?

J

[odie_trackie]

Ummmm, I don't think this is necessarily true. There sprag will always engage if the engine goes backwards. Whether or not the bike is in gear doesn't affect that.

I always start and stop the bike neutral (well, almost always).

Neutral is a pain to find on this bike, for sure.


Originally Posted by adam567265 View Post
It helps to shut of your bike while in first then in to neutral,then you dont hawe the kick back which helps the life of the sprag
its also easier to find neutral like this aswell .... am i the only person who finds it a bitch !





Dumb Question, do you mean I should be shutting down the bike in nuetral. I always try to start it in nuetral. Is this better?

J

[DarksideMspts]

....hey guys, new Aprilia owner here. This site is great, and this particular thread is awesome! It's exactly what I need to do to my RSV. The Ducati sprag is also a big help, as it's way cheaper then the oem Aprilia piece. Just wanted to say, great site, and great write up.....thanks, I'll see you around the site.

[Óriás]

Hy.I would like to invite you to our aprilia forum.We are from hungary.In the forum you can choose between english or hungarian.Please visit us : www.rsvforum.com
Thanks.

[Janky]

Hy.I would like to invite you to our aprilia forum.We are from hungary.In the forum you can choose between english or hungarian.Please visit us : www.rsvforum.com
Thanks.
:cheers:Sziasztok baratok!!!!!

[Arkansawyer]

Gathering all the bits together to repair my sprag and came across this little bit of info. KTM also uses this same sprag under PN 58440026000. I've priced it online from KTM World for $75.

[FalcoLion]

Gathering all the bits together to repair my sprag and came across this little bit of info. KTM also uses this same sprag under PN 58440026000. I've priced it online from KTM World for $75.

That is an awesome piece of info. That is cheaper then anything out there by at least 50%

[Arkansawyer]

That is an awesome piece of info. That is cheaper then anything out there by at least 50%

Here is the Ducati forum link where I found the info.....post #4.

http://www.ducati.ms/forums/showthread.php?t=59698

[Mike Moriarty]

has anyone verified that the KTM part is a viable alternative, other than the internet posts?

The part # definitely crosses to a sprag clutch.But will it fit the Aprilia?

[Arkansawyer]

Give me a couple more weeks.

I do have the KTM sprag but I haven't fitted it yet. My bike is in AR and I am still in TX. The weekend that I considered working on her it was cold, windy and overcast outside. No to mention the fact that I had just a few hours to complete the job before I needed to return to TX, made me put the job off until I has more time.

[Mike Moriarty]

Give me a couple more weeks.

I do have the KTM sprag but I haven't fitted it yet. My bike is in AR and I am still in TX. The weekend that I considered working on her it was cold, windy and overcast outside. No to mention the fact that I had just a few hours to complete the job before I needed to return to TX, made me put the job off until I has more time.

understood...I am going to order the KTM part today. I will let you know how it goes...

[Arkansawyer]

understood...I am going to order the KTM part today. I will let you know how it goes...

Gonna beat me to it. Let us know.

[Arkansawyer]

In AR now with the bike and got it over to my friends nice warm garage. Will start tearing it down tonight....look for an update in the morning.:cheers:

[Arkansawyer]

Update.....looks like the previous owner had a flywheel bolt come loose on him. Slight damage and doesn't look too serious. I know you guys don't want to hear the details of all this so I will respond back when I find out wether or not the KTM sprag fits or not.

[odie_trackie]

Make sure you get a plumber torch, the freewheel locking tool and the right locktight. Please post any observations as you go along. Maybe you will find an easier way to do some of the repair.

[Arkansawyer]

One item on the original write up by the forum member was removal of the clutch slave. It may allow a bit more access to the alternator cover it is not necessary to remove the clutch slave. I think someone else mentioned this in the thread.

Be sure and check the 3 flywheel bolts whilst your inside and loctite them.

[Mike Moriarty]

My KTM "freewheel" sprag clutch showed up yesterday in the mail.... it is in a KTM blister pack, but labeled "made in japan"

[DarksideMspts]

.....I also ordered the KTM part....it should be here any day now. I also, will let you all know how it goes. :happy:

[Arkansawyer]

KTM part is indeed a direct replacement. My old sprag was on its way out. As soon as I removed it from the "housing" a couple of the little rollers fell out and the spring is toast.

KTM part dropped right in...buttoning it back up now.

[pdxmille]

KTM part is indeed a direct replacement. My old sprag was on its way out. As soon as I removed it from the "housing" a couple of the little rollers fell out and the spring is toast.

KTM part dropped right in...buttoning it back up now.

DAMN good to know!!! How was it you decided that your old sprag was "on its way out"? I wanna know what to be listening for in the future...

[pdxmille]

My KTM "freewheel" sprag clutch showed up yesterday in the mail.... it is in a KTM blister pack, but labeled "made in japan"

you say this as if its a bad thing! I will be more than happy to buy a Japanese sprag when I need a new one!

now if it said made in china, I would be thinking twice about buying the KTM part...

[Arkansawyer]

DAMN good to know!!! How was it you decided that your old sprag was "on its way out"? I wanna know what to be listening for in the future...

It was not starting "clean". There are enough youtube vidoes out there of people starting their Mille's to be able to get a good idea of what it sounds like. If it were me and I wasn't sure that it had ever been done I would go in and replace it. If for no other reason to remove the three bolts holding the sprag housing to the flywheel. Loctite them propertly and re-install. If one of those comes out or loose there could be grave consequences.

One more note....be sure to put the sprag gear on the flywheel to check the direction of your sprag. I didn't and with the help of kzmille figured out which way it should go. For some of you I know that may sound silly but its things like this that I sometimes have trouble envisioning.

Lets add some torque specs to this as well:

3 small bolts that hold sprag housing to flywheel: 21.7 ft lbs
large bolt at the center of the flywheel: 94 ft lbs

Use green loctite 648 on the above bolts.

[Mike Moriarty]

you say this as if its a bad thing! I will be more than happy to buy a Japanese sprag when I need a new one!

now if it said made in china, I would be thinking twice about buying the KTM part...

Not at all, just noting that KTM sources this part from one of the japanese bearing houses...eastern Europe also supplies bearings. I am just happy it will fit.

[DarksideMspts]

.....I just finished up my sprag replacement. The KTM part does fit, just make sure of the rotation. There is an arrow on it, as well as the stock Aprilia part. Tke KTM part is opposite, but it has no flange, like the Aprilia part does, so you can just flip it over. I had the battery charging, while I was putting it all back together.When I was done, I bumped the starter button....and she roared to life! I repeated it several times....no problems. Sweet! Time to start riding her now. :happy:

[ZdaMan]

.....I just finished up my sprag replacement. The KTM part does fit, just make sure of the rotation. There is an arrow on it, as well as the stock Aprilia part. Tke KTM part is opposite, but it has no flange, like the Aprilia part does, so you can just flip it over. I had the battery charging, while I was putting it all back together.When I was done, I bumped the starter button....and she roared to life! I repeated it several times....no problems. Sweet! Time to start riding her now. :happy:

How much did you pay for the KTM part?

[DarksideMspts]

....a cool $73 bones..... :D

[ZdaMan]

Damn. Lot cheaper then the Ducati part.:bangwall:

[DarksideMspts]

....yeah, WAAAAAY cheaper, for the same part. If I really wanted to, I could've rebuilt the factory piece, with the KTM part....but I didn't really see it necessary. My drive gear, and sprag housing were a little scarred up, but I dressed them up with some emery cloth, and they are perfect. No crunching, or any abnormal sounds....just the sweet, thumping pulses, when that big V-twin fires up! :peace:

[imdrax]

Im curious if most of you simply replaced the sprag itself and opted not to replace the housing and gear?

[odie_trackie]

I replaced the housing because it was obviously done. The gear was not so I left it. The sprag was also obviously done. The manual spells out the wear limits so it's easy to make a solid determination if the part is done or not. The sprag is not so easy to judge, but if you get the cheap (thanks to the work of folks on this forum) sprag, you might as well change it.

I could see the housing and the gear being fine and just the sprag being done. But you gotta get in there and inspect the parts.


Im curious if most of you simply replaced the sprag itself and opted not to replace the housing and gear?

[imdrax]

OK thanks, for now Ill order the KTM part(Found online for $63 BTW) and then tear her down and see how everything else is. As far as AF1, are they fast shippers?

[DarksideMspts]

....dang, $63?! I got mine from KTMworld, or something like that....lol. I also tore mine down to see what I was gonna need, exactly....first. I determined I was only needing the sprag. The housing, and gear, were still in spec....so I just dressed the surfaces with some emory cloth, and replaced the worn out sprag. Done deal, it works perfectly now.

[Arkansawyer]

As far as AF1, are they fast shippers?

Like greased lightning.

[imdrax]

Thanks, yeah they shipped quick. Im curious now looking at the flywheel puller how it is actually functional? Im used to automotive"pullers" and to me this looks just like a center bolt for a puller. Is that correct" will I need to go out and rent a puller set? Or can someone show me a picture of how I actually use this bolt.

[kzmille]

The flywheel is threaded for the puller bolt.

[imdrax]

Yea I get that, but how does the bolt "pull" just by threading in. I'm trying to invision the bolt pulling the flywheel out all on it's own.

[Arkansawyer]

Thread the puller "bolt" into the center of the flywheel. It will draw it off the shaft if that makes any sense.

But first make sure you have the flywheel bloody hot with a propane torch.

[Arkansawyer]

Yea I get that, but how does the bolt "pull" just by threading in. I'm trying to invision the bolt pulling the flywheel out all on it's own.


Because the bolt bottoms out the only thing that can give is the flywheel which will climb the threads and pull itself off the shaft.

Remember a screw is just a modified incline plane.

[kzmille]

The puller threads into the outer and of the flywheel hub and the bolt end pushes against the end of the crankshaft pushing the crank out of the flywheel.

[imdrax]

Ok that makes a little more sense. I should be tearing into this later this week. I read in another thread about using the rear brake and putting it in first gear to hold the crank. That sounds better than having the tdc bolt shear off. Has anyone else done this.

[kzmille]

If you are going use the rear brake, putting it in a higher gear will work better than first.

I've never heard of anyone shearing the crank holding tool though.

[imdrax]

Yea I figured. Any recomendations on how to do this on the kickstand? Or simple way to prop the bike straight up without a stand?

[kzmille]

No, I'd recommend you buy or borrow a stand. If you have or can borrow some jack stands you can run a steel rod through the swing arm pivot or rear axle and set it on the stands.

[imdrax]

Yeah i have jack stands. GOOD IDEA!! That was exactly the answer i was looking for thanks. Im sure I would have thought of something like that eventually haha.

[Arkansawyer]

Its 1/2 inch solid bar that fits through the swingarm pivot. I "rented" mine from Lowes to use when I swapped out my rear shock. I say "rented" as I promptly returned the bar after I was finished with it and got my money back.

Yeah....I'm a cheap bastard.

[imdrax]

I constantly "rent" tools.

[ZdaMan]

My TDC locking tool had a bad thread or two on the end. Could not get it to start. Thought I was doing something wrong. I had to clean up and rethread it a bit then it was good to go.


In case anyone needs Loctite 648 here is where I ordered mine. Reasonable shipping too.

http://www.greenskyadventures.com/loctite/loctite.htm

[imdrax]

Is that loctite not readily available at part stores?

[pdxmille]

nope, it isnt....

[Arkansawyer]

I found the loctite green at several auto parts stores. It wasn't the unobtanium I thought it was going to be.

[imdrax]

I can find permatex green very easy, is it the same as loctite green?


http://www.google.com/url?q=http://docs.google.com/viewer%3Fa%3Dv%26q%3Dcache:HlV-VvJvlYcJ:www.permatex.com/documents/tds/Automotive/29000.pdf%2Bgreen%2Bpermatex%26hl%3Den%26gl%3Dus%2 6sig%3DAHIEtbR2dC73eXqT9eGLCquFyqYp-K6aYg&ei=3B-QS7qeLJCStgPNyOSnCA&sa=X&oi=gview&resnum=2&ct=other&ved=0CBYQxQEwAQ&usg=AFQjCNEj2Ddcy0TliF226curEzctY3OUdQ

Or

http://www.google.com/url?q=http://docs.google.com/viewer%3Fa%3Dv%26q%3Dcache:XxmWdbpmj10J:www.loctit e.sg/sea/content_data/93769_Loctite_648_Retaining_Compound.pdf%2Bgreen%2 Bloctite%2B648%26hl%3Den%26gl%3Dus%26pid%3Dbl%26sr cid%3DADGEESjWgzuQUZ5SVWA9BTXN_Nq0nInUYm5D_zjdQQnR 1O3nNqxliCBHopfD37JKrkRkrLup0rNZupBJI7vp1N08S83T3-VFxEF54xe-kr1T8AjtqnGqeJcdjcY5FrexPeiF3DmFR9KT%26sig%3DAHIEt bSLxU3JFDds-_ZT9JXYvvW99wn0-w&ei=PCCQS_XMJoqStgPPlIjXCA&sa=X&oi=gview&resnum=2&ct=other&ved=0CBgQxQEwAQ&usg=AFQjCNEGszAn5s58WYTETLZxGdQiNKTKMQ

[kzmille]

The permatex penetrating green is definitely not the same as Loctite's 648 green. Loctite makes a penetrating green as well. The penetrating greens are for applying to already tightened fasteners and are not a substitute for 648.

[imdrax]

OK well I think I am going to just use threadlocker Blue from permatex. I dont see much of a difference in toque and heat ratings to justify $35.

[kzmille]

Not sure which location you are talking about. Blue would probably be okay for the sprag housing bolts and crank bolt - not recommending it mind you - but for the crank taper I would say to stick with the 648. You don't want the flywheel falling off. Best to use 648 on all recommended spots.

[imdrax]

So after some digging on the "net" I found that Permatex 64000 should be an equivalent.

[imdrax]

BTW Im looking through the FSM and cannot find the section on this. Anyone know page number? or section number?

[imdrax]

Im trying to remove the flywheel nut as we speak and by putting it in 6th gear with my foot on the brake the flywheel just spins freely. Its spinning without the gears as well. any advice?

[odie_trackie]

That ain't gonna do it (but you already new that). :)

You need a flywheel locking tool (http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=3168) from AF1. It's $5.00 and worth every penny.

Start calling around otherwise you gotta wait for AF1.


Im trying to remove the flywheel nut as we speak and by putting it in 6th gear with my foot on the brake the flywheel just spins freely. Its spinning without the gears as well. any advice?

[imdrax]

Actually one of the gears wasnt engaged, once i engaged the gear it came right off. Now i cant get the flywheel out!!! IM using a propane torch will that get it hot enough? Because Im heating the flywheel surface up for about 5 minutes but its not budging.

[imdrax]

Anybody? I went and bought some MAP/PRO gas which is supposedly 3x hotter but its still not giving.

[Arkansawyer]

Have you threaded in the flywheel removal tool where you just removed the flywheel bolt?

Have you heated that sombitch up nice and hot?

Then put some muscle into tightening the flywheel removal tool and it should pop (literally).

[Arkansawyer]

I've just had a buddy look at the thread locker that I used and it was Permatex penetrating green. I've looked over the material from Permatex and I'm not going to sweat it.

[imdrax]

Yeah Im holding the torch to it for literally 5 minutes and it doesnt change colors or anything. Im almost afraid to put to much to torque into it and shear off the tdc crank holding bolt. here is a picture of what my puller looks like, its the af1 cheaper one.
http://farm5.static.flickr.com/4028/4409918004_151aaa83dc_b.jpg

[imdrax]

I've just had a buddy look at the thread locker that I used and it was Permatex penetrating green. I've looked over the material from Permatex and I'm not going to sweat it.

Just went another go around and the puller started to turn but no POP. Instead nice shavings started coming out, WTF. I have no idea how everyone on here got their flywheel off so god damn easy. I believe I am officially over it. I think nothing short of going to buy an oxy acetylene torch is going to get this thing off.

[imdrax]

Ok well not to keep cluttering this thread up but I called 2 local Aprilia Dealers and they both said the same thing, Heat. Well I guess there is nothing I can do because the threads separated in the flywheel and I do not want to run the risk of ruining the shaft threads and then not be able to thread the actual flywheel bolt back in. Its extremely hard to believe I am the only person to have this much trouble, and I tell you I heated the living shit out of the center of the flywheel. I am going to button her back up and GOOD RIDDANCE. Already sick of italian, I'm ready to jump back on a gixxer. Thanks.

[Arkansawyer]

Look man we've all been there frustrated with something mechanical or electrical that doesn't respond like we want. You can either throw your hands up and quit or keep trying.

You want to blame the motorcycle but honestly I think you need some help from someone to accomplish the task. Maybe someone with a little experience.

[imdrax]

I agree I was totally frustrated, however no more of an experienced person would have anything better to accomplish the task. I mean think about it, you heat the flywheel, then thread a bolt, there's not much more to it. But when the threads on the flywheel separate from using a factory service tool to remove said flywheel there is an inherent flaw in the procedure or engineering.

It once took nearly 500 lb/ft of torque to break loose my IS300 flywheel bolt , but you know what, it came loose with the proper grade socket and a 10ft pipe. This flywheel on the other hand relies merely on a few thin threads to absorb the grunt of the massive amounts of torque needed to remove it. This is why most applications for removing a flywheel use a puller with a base plate and JAWS so that there is a hardened tool there to absorb the force needed to separate the components rather than the threads on a flywheel.

I would like to lastly say that I would strongly recommend NOT using the AF1 "alternative" puller. It is obviously not made for this application and in fact the bottom threads on it were lathed off while being turned against the gear shaft. It comes packaged as a Honda puller. Spring for the $45 Aprilia genuine tool, I wish I had. Over and out and unsubscribed.

[kzmille]

Did you put any kind of lubricant on the threads and tool end before trying this?

[Arkansawyer]

I think I would have threaded the bolt then heated everything up.

[FongP]

Sorry if this is a dumb question, but is the KTM sprag clutch gear the same as ours as well?

[Arkansawyer]

It is. It just needs to be flipped over.

[FongP]

ok. so let me continue my idiocy. out of these parts:
AP0634595 - Sprag Clutch Gear
AP0659123 - Sprag Clutch Housing
AP0659110 - Sprag Clutch
AP0295830 - Ignition Unit 12v380w

All I need to get from Aprilia is the housing right? The sprag gear and sprag clutch from KTM are totally ok?

I dont even know what an ignition unit is. Ugh. I'm such a dumass.

[kzmille]

I think the only part you can use from other bikes is the sprag itself. The gear and housing must come from aprilia.

[FongP]

aw man!

[odie_trackie]

I dont even know what an ignition unit is. Ugh. I'm such a dumass.

Just FYI: The Mille ignition is controlled by the ECU (engine control unit) via four coils (two for each cylinder) that in turn send high voltage to the spark plugs.

They are four roughly cylindrical shaped pieces the size of a frame slider. They have three wires connected to them. There are two small wires which are the signal and the ground wire and the third is a pretty thick wire which is the actual spark plug wire. These are the so-called "ignition units".

The OEM part comes with the coil and the plug wire. Evoluzione sell just the wires and spark plugs with out the coil, which is a much better deal.

Somewhere around 18-19k miles, my Mille started to run pretty rough. Replaced the wires and plugs and Viola! She ran like a top.

I know you are messing with the sprag, but I figured learning more about the ignition system couldn't hurt. Maybe help you alleviate your alleged state of dumb-assness. :)

[kzmille]

The ignition unit he is referring to above, pn 0295830 (http://www.af1racing.com/store/Scripts/prodList.asp), is actually the alternator stator. Not to be confused with the coils. It isn't really part of the whole sprag problem but it is sometimes damaged if the sprag bolts come loose.

[odie_trackie]

Oops. Sorry, my bad.


The ignition unit he is referring to above, pn 0295830 (http://www.af1racing.com/store/Scripts/prodList.asp), is actually the alternator stator. Not to be confused with the coils. It isn't really part of the whole sprag problem but it is sometimes damaged if the sprag bolts come loose.

[NorCalRSVR]

Thanks to the OP for this and to the rest who posted their experiences. It made things a bit easier knowing what I was in for. I got the fly wheel off, just waiting for it to cool enough to work with so I can get the sprag clutch out. It took quite a bit of heat to get the fly wheel off. SO, a word to those attempting the job. GET IT HOT! I don't mean heat it for 5 minutes with a propane torch. I tried 5 minutes first, it didn't budge. I tried 10 minutes the second time, still didn't budge. The third time, I let the MAPP torch sit for 15 minutes. I threaded the puller in and voila! No torque was needed at all, the puller turned easily and the fly wheel came right off. Just a tip here as well...wear gloves (duh!) the fly wheel will be very, very hot. I made sure I wore my mechanics gloves just for that reason. As for the puller, just order the after market one from AF1. I got mine direct from the manufacturer but you'll pay the same price from AF1. The MFR of the puller is local to me so it was kind of a no brainer to just get it from them. If you use enough heat, you should not have to put any torque at all into the puller. Also, just a couple of observations I made during the course of my "project" that may help the next guy/gal in doing this repair themselves:

1) If you raise the tank, the alternator connector is on the right (brake side) of the bike, next to the frame. Picture below. Once you disconnect it, you have sufficient slack to swing the alternator cover over and hang it from the frame slider. No bolt removal etc. Also, if done prior, the gasket won't tear so you'd save yourself some headache there.
http://i96.photobucket.com/albums/l178/NorCalRSVR/Gixxer%20Project/DSC00853.jpg?t=1275176107

2) There are wrench flats on the fly wheel hub. The measurement is 1 9/16" which is large but being that I was a heavy equipment mechanic at one time, I have some big a$$ wrenches in my tool box. Using that to keep the thing from turning and a 14mm allen bit socket, I got the flywheel bolt out with little issue. A big crescent wrench would most likely do the same thing. Mine was too tight to take advantage of my impact wrench as my small compressor doesn't deliver enough CFM to create that kind of torque from it.

3) I did not drain the oil. All I did was unbolt the reservoir tank and remove the small hose from the top of the tank. That was plenty sufficient to lower the reservoir out of the way. I did however, place a drain pan under the bike to catch the little bit of oil that I did lose when I popped the alternator cover off. Pictures to follow...I'll just insert them into this post once I get them to my photo bucket.

I'll report back tomorrow sometime after I figure out what I'm going to need for the Sprag Clutch....sean
__________________

[NorCalRSVR]

Repair Complete!:banana:

I got the new sprag from North Bay Motorsports in Santa Rosa yesterday. I got the KTM one and as previously identified, the arrow does in fact point the wrong way. I flipped it over as directed and after applying a thin film of oil to the sprag "teeth" I inserted it into the housing and bolted it to the fly wheel. 2 things of note here that may interest anyone doing the repair.

1st off, when I pulled the screws for the sprag clutch housing out of the flywheel I noticed that one had flattened out threads and another some thin wire like bits of thread came out of the hole. What discovered was that the 6 holes in the fly wheel are not equally spaced. I put the housing up to the flywheel in the position it was installed and two of the holes were not centered while the third was. I rotated the housing until I got all three threaded holes centered in the flywheel holes. I marked one hole on both the housing and the flywheel to match up once I got the sprag installed.
http://i96.photobucket.com/albums/l178/NorCalRSVR/Gixxer%20Project/DSC00849.jpg?t=1275176368
2nd; after noticing that the threads on two of the bolts were bunged up, I immediately decided to buy new ones. I also found that the stock bolts were grade 8.8. I went to ACE Hardware and found that they carried grade 12.0 bolts in the correct length and thread (8mm x 16mm x 1.25) I replaced my stockers with these bolts.
http://i96.photobucket.com/albums/l178/NorCalRSVR/Gixxer%20Project/DSC00845.jpg?t=1275176410
Thank you, to whomever posted the Permatex part number of the thread locker. I found a single tube at my local auto parts place, as the local industrial supply house didn't have the loctite branded one.

Other than that, it was as straight forward as described by the OP. I had a more difficult time putting the alternator cover back on without the gasket falling off than I did any other part of this job.

I do have a tip for that, and that is use some grease on the engine mating surface, and some good quality RTV on the alternator cover mating surface. Stick the gasket to the alternator cover and then put two bolts through to hold it in place. Once you finally get the cover finagled into place, you already have bolts there to start threading in. Further, if you have to do this job again, the side with the grease should release easily and not tear the gasket, while the side with the RTV should hold the gasket in place and not give you fits trying to ensure it doesn't go astray and tear. .......sean

[ghostrider71]

Gathering all the bits together to repair my sprag and came across this little bit of info. KTM also uses this same sprag under PN 58440026000. I've priced it online from KTM World for $75.

Looks like KTMWorld has increased the price to $79 + shipping. :soap::soap:

Anybody have another good source? Where did imdrax get that $63 Sprag?!

I think I'm going to have to bite the bullet and DO this soon....mine is making some AWFUL sounds. :rolleyes:

gr

[vr6extreme]

Just finished my sprag replacement. I went with the Ducati sprag.
I also used the recommended Aprilia tools. The long wing nut screw is the best to use in my opinion. It just held everything perfectly in place.
I noticed that if I applied the heat all the way around for about 8 min using my propane torch the flywheel just slide right off using the flywheel tool.
I took a ton of pic's as well

Thank you to everyone that posted on here. It helped me big time

[DanV990]

The sprag clutch in my 2000 RSV Mille with 26,500 miles just gave up the ghost on Friday. I had a whole weekend, plus my vacation this upcoming week, of riding on the Aprilia planned. After reading this great thread I have decided to do the repair myself and I'll be ordering the KTM Sprag. Looks like I'll be spending my vacation turning wrenches on the Aprilia instead of carving corners with it.

Vr6extreme you said you have a bunch of photos of your sprag replacement. Would you be able to post some or PM them to me please?

[vonDutch]

I think the only part you can use from other bikes is the sprag itself. The gear and housing must come from aprilia.

It seems you can use the starter gear of an early model (late 80's, early 90's) Fireblade as well. Unfortunately I don't know the part number, but on the Dutch board I've read about a couple of guys who have been using the Honda gear.

[DanV990]

The replacement sprag has been in my 2000 RSV Mille (the early model with steel gas tank) about a month now and I have over 800 miles on it since the repair.

For the sprag clutch I used KTM Free-Wheel part number 58440026000. I bought it from ktmworld.com for $79.69 plus 9.40 shipping. I used the Aprilia Sprag housing http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=2837 $139.99.

When I pulled the stator cover off my 2000 RSV Mille I found that one of the three bolts that attaches the sprag housing to the flywheel sheared off from fatigue (bolt was loose) and trashed my stator. The other two bolts were quite loose and showed no sign of loctite.

I replaced the stator for $140 with the unit from Rick's Motorsport Electrics. I spliced into the original 3 wires for the stator at 3 inch intervals about 6 inches from the stator cover. I used the original wiring for the flywheel position sensor and had to cut channels into the rubber grommet on the replacement stator leads because the one from Rick's only has 3 wires instead of the 5 on the original. Apparently the newer bikes have a separate port in the stator cover for the position sensor.

Removing the Flywheel took about 5 minutes of heating the taper with a propane torch and the flywheel removal tool inserted and snug. As soon as it was heated up enough it came off with very little force, just one or two turns with a 12" long wrench using medium pressure.

On reassembly I used Locktite 648 on the Flywheel taper and the replacement sprag housing bolts. The original sprag housing M8x16 bolts were grade 8.8, I replaced them with grade 12.9 and torqued them to 32 NM (used the lubed torque rating for an M8 12.9 bolt due to the loctite on the threads http://www.cncexpo.com/MetricBoltTorqueNm.aspx)


The bike runs better than ever. The engine revs more freely and seems more powerful. Start-up is very positive and draws less power from the battery to crank the engine over. I have not had the dash board reset on start-up since the sprag and stator replacement.
http://i769.photobucket.com/albums/xx336/Kragges/Aprilia/IMG_0158.jpg
http://i769.photobucket.com/albums/xx336/Kragges/Aprilia/IMG_0166.jpg

[RSVRye]

2000.5 Mille-Just wanted to put my 2 cents in (some of the info is in this thread, some in others, some not).. I found out after going to 6 hardware stores, and a bolt specialty shop that is very hard to find a bolt to use as the TDC locking tool as it has to have threads from top to bottom, I finally just went with a piece of all-thread, the size is M8 and needs to be 1.25 pitch and at least 100mm long (80mm will not work). I hand tightened it as far as it would go. I used a drinking straw in the spark plug hole closest to the stator side to get close to TDC first. Then if you lay down next to bike on the stator side and reach one had under to the other side, and try to keep slight turning pressure on it, while using the other hand to slowly turn the flywheel, it'll click into place(reminds me movie where they line up the pins to crack a safe.) Then just go to the other side and screw the bolt/TDC Locking Tool/All-thread the rest of the way into the crank and wah-la. The v990 manual says not to use an open flame torch on the flywheel, to use a hot air gun for 5-10min. I had both, so I figured I'd try the hot air for 10min first, and it came right off using about 30-40lbs with a 1/2in drive breaker bar. And found, after it cooled!, that all my gears we're fine and tolerances within spec. My sprag was so worn out though, that the I could easily pull the spring off holding the bearings. I used the KTM sprag, and the pemetex threadlock equivalent. I put it all back together and it works like a charm, stonger starting than ever. I would recommend that after everthing is back together to let the threadlocker set up overnight, you can also use this time to charge your battery up. Well my two cents turned into like a buck 25.

[chipbankr]

man i need help chang the sprag clutch put all back and now its hard to start got new bat n new oil get kick back some times too but bike was running fine when the sarter just spins so i found out it was the sprag so i changs all tree parts and now im stuck so if anybody knows pls give me acall not good on typing its sat 3/12/2011 need to talk to some one today thanks 931 287 3990 need help bad

[chipbankr]

i have 2007 rsv r bike ran fine to i found out that sprag clutch went out starter just spins so got all tree parts so i park the bike week end came went to do the job like it said in the book put all back put new oil new filter new parts new clutch n housing new gear now the bike wont start has hard turn over seems like its draining the bat all so have new bat as well can anybody help me dont know what i did wrg can any body call me my # is 931 287 3990 need help bad

[vsho]

When you replaced your sprag clutch with the ducati one, does it matter what year your bike is for this, i have a 2002 aprilia rsv mille 1000. ????

[DanV990]

When you replaced your sprag clutch with the ducati one, does it matter what year your bike is for this, i have a 2002 aprilia rsv mille 1000. ????

The Ducati part will fit in your 2002. So will the BMW and the KTM.

[vsho]

What site can i go to, to get the ktm sprag clutch, not use to buying parts for this bike, this is my first bike?

[02mille99expy]

hey guys... not to drag this out... but my sprag failed the other nite so the bike has been parked... ordered ktm sprag and looking to find more info on the flywheel puller... i understand i can use the threaded rod for the holder... but as for the puller the least expensive one i found is 45 plus shipping from af1 and that would be fine if i didnt wanna fix it asap and wait for the puller.... ne ideas on a bolt(size and pitch) that would work for this ??? im hoping to do it this weekend and i work at a parts store so wondering if their is a suitable alternative... any help would be greatly appreciated...

[seehog]

MOTION PRO part #08-0074 it's what I used.Lists for $8.95

[DanV990]

but as for the puller the least expensive one i found is 45 plus shipping from af1 ...

Here is the 14.99 flywheel puller on AF1. It is the one I used. I guess you did not search very hard on the AF1 site. It also works for various years of Hondas so you may be able to find one at a local Honda dealer if you do not want to wait. The stamping on the head is MP 08-0074 so as the previous poster stated it is a Motion Pro tool and you may be able to find it locally or cheaper than AF1 has it. The thread size is M22x1.5 RH.

Here is a list of the Honda & Kawasaki bikes that use this puller from the motion pro site and the Honda equivalent part number.


Honda: FT/GB500, NT/NX650, TL250, VF700C 84-86, VF700F/S, VF750C 82-83, VF750F/S, VF1000F/R, VF1100C/S, VFR700/750F 86, VT500C/FT, VT600C/CD 88-89, 91-96, VT600C/CD/CD2 97-02, VT750C/CD/CD2, XL250/350/500/600, & XR500/600/650L
Kawasaki: KLR 600A 84-86 AND KLR650 1996 and up
Equivalent to Honda tool 07933-3290001



Here are links and photos for it on Motion Pro's site and AF1

http://www.motionpro.com/motorcycle/partno/08-0074
http://www.motionpro.com/images/items/08-0074.jpg

http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=1634
http://www.af1racing.com/store/ProdImages/AF1-v990-flywheel-puller.jpg

[02mille99expy]

ok ordered it today along with the new alt gasket... just wanted to let ne one know who is going to do this with the KTM replacment that www.powersportswarehouse.com has it for 62 bux plus shipping...
http://www.powersportswarehouse.com/fiche_select1.asp?cat=Motorcycles&mfg=KTM&mfg1=KTM&partnumber=58440026000
ne who... will keep everyone posted as soon as i do the swap... as for now... stuck riding my r1 LE.... :(

[02mille99expy]

also wanted to let ne one who is doing this kno... that the size on the flywheel bolts...M8x16x1.25... i got some 12.9 hardened from a local fastenal for 32 cents a piece.... i kno their not a problem usually on the 02s like mine... but for the 1.50 i figured i would replace them ne ways....

[Hollywood7]

anyone know where to stick the crank stop tool in at? the manual is know help

[kzmille]

From the shop manual:

[Hollywood7]

anyone know if the bolt on the crank is reverse threaded?

[kzmille]

There are no left hand threads on these motorcycles. None.

[go_modem_go]

There are no left hand threads on these motorcycles. None.

I just found out that there are at least three left threaded parts on a Rotax V990 engined Aprilia - on the Falco gear lever rod, the front ball joint thread, rod thread and stop nut are left threaded!... ;)


Digging up this topic:

I'll be attacking the sprag clutch repair as a precaution - it's been in there for 12 years and 60k kms now, and gave me the occasional crunch & horrible starting sound on weak battery conditions for many years.... I would need to replace those 8.8 screws anyway...

As to the KTM 640LC4 (and many others) sprag clutch part N° 58440026000: Is everyone's KTM sprag clutch still ok?

If yes, I'll be buying that KTM one, at €70.- incl. shipping and taxes.

It certainly comes MUCH cheaper than the well over $450.- shipped & taxed for the very same part from Aprilia (http://www.af1racing.com/store/Scripts/prodView.asp?idProduct=2838)... :soap:

PS: Beta Part N° 3625197 000 is the same part than KTM - interchangeable. It is even cheaper, at €53,78 net... ;)

Bikes that have this fitted as well: Beta Motor S.p.A. RR 250-400-450-520 with KTM engines, enduro models 2007-2009. Interesting for Europeans, I guess, since there is probably much more local Beta Motors shops around and about than in the USA.

[kzmille]

I just found out that there are at least three left threaded parts on a Rotax V990 engined Aprilia - on the Falco gear lever rod, the front ball joint thread, rod thread and stop nut are left threaded!... ;)

Well you've got me there.

[DanV990]

As to the KTM 640LC4 (and many others) sprag clutch part N° 58440026000: Is everyone's KTM sprag clutch still ok?

If yes, I'll be buying that KTM one, at €70.- incl. shipping and taxes.

.

I have over 17,0000 miles (27,400 kilometers) on my KTM sprag 58440026000 and it is still going strong. I put it in my bike around 26,000 miles and I now have over 43,000 miles on the clock.
It engages the first time, every time, the starter is used with no clunks or other unusual sounds.

[go_modem_go]

I have over 17,0000 miles (27,400 kilometers) on my KTM sprag 58440026000 and it is still going strong. I put it in my bike around 26,000 miles and I now have over 43,000 miles on the clock.
It engages the first time, every time, the starter is used with no clunks or other unusual sounds.

Excellent.

I just bought the same KTM part, as Beta N° 3625197 000 from a German Beta Moto Motocross Online Parts shop - for €53,78 net, plus taxes and €3,95 shipment.

Let's hope this will last another 12 years and 60k kms, like my first one (which is on its way out).

[go_modem_go]

Hi,

I need to resurrect the thread again - maybe someone can help me.

I f*cked up the flywheel thread with the puller - despite tons of heat, and use of the correct 22x1.5 motorcycle flywhweel pulling tool (Buzetti type). :spankie:::bond:

Anyway, the pulling tool is stuck in there.... Thread of the Rotax flywheel centre is all mushed up - it just didn't withstand the torque (I used a 70cm torque wrench with 14mm long socket to puller - when it clicked at 140Nm, I continued to apply more torque, flywheel still wouldn't budge a mm...).

http://img641.imageshack.us/img641/3811/sdc11092e.jpg

PS: The two keys are there due to one of my later (futile) attempts to get the pulling tool back out (keys used as handle whilst wrenching the puller back out... )

1.) How do I remove the flywheel now??? :confused:


I tried with some wooden support and an iron bar pulling from the back, to no avail (despite 5-10mins of heat to the flywheel centre from a plumbers butane torch). This f*cker seems like welded to the engine crankshaft, but no one has fiddled with it ever before (engine never opened b4!)

2.) I just ordered an entire 2006 Tuono MkII replacement flywheel assembly including gears (10k kms, €110.- shipped - much cheaper than ME / RP used parts!). I wouldn't want to re-use the damaged old flywheel (provided I ever get it off! See above! :D)....

I know it is a slightly different assembly - hopefully an improved one. Flywheel seems much lighter, but it has a far larger sprag clutch housing plate attached to it in the back.

But: Will a RSV-R / Tuono MkII "RR" 2006 complete flywheel assembly work with the Falco PA, resp. Mille ME / RP 1998-2003 engine stator? :confused:

184065184068

I looks pretty much the same overall size, from the parts fiche the 2006 Tuono MkII stator side looks similar to early Mille / Falco, except the electrical connector. Freewheel gears are the same part N°'s as well, as is the actual sprag clutch assembly (I have a brand new KTM / Beta one in stock, for the future...).

I just hope the crankshaft stub & flywheel magnet inside diameter, magnet depth and stator location are the same for all V990 Rotax engine generations!

Thanks for any tips & hints... :)

EDIT, PS: I have just learned that the RSV-R "RR" / Tuono MkII flywheel assembly doesn't work on early engines up to 2003 (RSV ME & RP) resp. 2005 (Tuono RP, Falco PA).


Whilst it would fit mechanically, it gives more rev pulses - the Rotax-Bombardier ECM only needs 6 pules per rpm, whilst later engines emit MUCH more than that. This would mess up the engine management... Caponord and Futura seem to have different pulses as well (they use a SAGEM ECM).

[imdrax]

I had a 2002 rsv Mille r that had this issue a while back, I just picked up a 2004 1000r non factory that has a light clanking noise on startup like my old Mille. Is there a writeup for the 2004+ or is it nearly the same as this DIY? Were the 2004+ known to fail jut as commonly as the milles?

[go_modem_go]

@imdrax: Mechanically, it's pretty much the same construction.

The sprag clutch itself is exactly the same one.

What has changed is the mounting flange on the back of the flywheel, it has 6 bolts on the RSV-R RR-type engine, instead of just 3 bolts that were very prone to failure on early bikes (Aprilia used cheap 8.8 bolts in 1998 until at least 2000/01, if not a whole while longer - these can sheer off!). On the RR version, it's also backed by a massive 2nd metal rim - all in all, this looks more sturdy than the flimsy 3-bolt rim on early models.

But I have no idea if the 2004+ RSV "RR" is as failure prone. From a purely sprag clutch point of view, it should be - but at least you won't get sheered off bolts and stuff like that. Also, it's engine / ignition management system is much more sophisticated, hence you may have less off a chance for the engine cranking backwards when not firing up immediately (that's a killer on the sprag clutch!)

[go_modem_go]

Hi,

I need to resurrect the thread again - maybe someone can help me.

I f*cked up the flywheel thread with the puller - despite tons of heat, and use of the correct 22x1.5 motorcycle flywhweel pulling tool (Buzetti type). :spankie:::bond:

Anyway, the pulling tool is stuck in there....

To anyone who gets into the same mess with a stuck puller screw, I fabricated the solution out of a metal bar, hydraulic jack, triple hook puller, wire and some half-drunken amateur "ingenuity":

184682

Link to post in Falco forum (http://www.apriliaforum.com/forums/showthread.php?245234-Flywheel-amp-sprag-clutch-removal-messed-things-up-need-help-amp-hints!&p=3052788&viewfull=1#post3052788)

[resqav8r]

Stupeo said "The Aprilia crank holding tool, bought from an Aprilia Main dealer was wrong" .. well that might explain my problem during my 04 RSVR sprag repair.

I may have gotten a lot wrong but doubt it'll affect the repair. The manual must have been written in Italian and translated to Chinese before being translated to English because much of it lacked detail and required assumptions and interpolation (so please pipe in if any of you see something really wrong or has a better suggestion).

My FIRST snag; locate and lock in TDC on either cylinder.
Sounds simple enough .. shift bike into top gear and rotate wheel several times till I know what max resistance feels like (ie valves closed and piston at top). Remove M8 bolt and insert tool ($32 bolt from AF1 http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=3168). Problem is my tool (wing bolt) arrived BLACK anodized and although it looks identical and treads in perfectly it may not be holding things as required? (how do I know it went in properly … it’s tightened till the wings catch the casing yet 4mm of thread is still exposed)

I ask this because when I go to tighten the flywheel puller (thanks to this post I’ll apply heat tomorrow) the crankshaft still turns and the piston goes down.

SECOND Snag; the manual does not indicate that the flywheel should be pulled as an assembly with the sprag (i.e., leaving the 6 bolts holding the gear inside the flywheel tightened). I assume I should leave them tight and pull the entire assembly (flywheel, bolts, gear, sprag) as one but I rightly don’t know.

THIRD Snag; Do I assemble the gears and sprag onto the flywheel and then install as one unit onto the shaft … again my manual isn’t particularly clear on this .. OR .. do I install the components onto the shaft and then install the flywheel over the top of them?
T
hanks for your help .. BTW IMO the OEM Aprilia Ignition Cover Disassy Tool -#0277252 is an unnecessary item that does little … I may change my mind after installing the cover but doubt it. Also I saved by using the BMW 650 Sprag but got my gears from AF1 .. which cost TONS more than losthaga & adam indicated on this thread.

[resqav8r]

i have 2007 rsv r bike ran fine to i found out that sprag clutch went out starter just spins Okay .. this may (or may not) be a clue .. search in this forum for BMW 650 sparg replacement .. I recall that the BMW engine spins in the opposite direction so you must flip all the bearing lobes before installing it on the Aprilia ... DOES ANYONE know if this is he case with the KTM sprag or the DUC sprag?

[resqav8r]

YEP we all got this diagram in our manual but "but tab A into slot B" isn't really much help for me. The 80mm is not enough .. you need 100mm is of help except I'm so retarded that I still need just a little more explaination ... i.e., does this tread into a rotating part of the engine or does it just slot into a bigger opening to prevent moving? If done correct will the crank still turn when I try to tighten the puller onto the flywheel? I assume if it does then my bolt from AF1 is only 80mm and not 100mm OR I've not gotten TDC correct?

[resqav8r]

brilliant (the pic with the floor jack mounted on the side of the bike with gear puller and metal fence post) ... I think at this point I would have just hooked a chain to the bumper of a truck and given it a yank ... hope mine comes off easier :bangwall:

[kzmille]

If the tool wing nut has contacted the primary cover you have totally missed the crank web. should be about 10mm from the cover with the slot engaged. you did not have the engine at TDC.

Nothing personal but service manuals are written for mechanics, not for novices.

You pull the entire assembly and reinstall as a complete assembly.

The tool 0277252 is a handle, nothing more.

[kzmille]

Posted the above after reading only post 159. There are two slots milled into the side of the crank web each one corresponding to TDC on one cylinder.

I have to go help make supper but if you have any other questions I can check in later.

[resqav8r]

Thanks KZ .. yes, I gather that the manual assumes some basic knowledge (I have an A+P) but we all know what happens when we assume so I thought I'd ask and thank you for clarifying .. Guess I'll have to find TDC the old fashioned way by feeling for the piston via the plug hole (so my TD shortcut didn't work). And also thanks for clarifying the part about it going on + off as a complete assembly (the book leads in that direction but doesn't say it). The part about "the Tool" was just me joking because yes .. it's a $40 handle and not a tool ;-) and it may be handy when I put it together. Cheers, AB

[kzmille]

Sorry if my choice of words was poor. What I meant to say is that most engine and general service manuals are written to provide essential basic info about about a specific mechanism that may have unique characteristics not seen before. It generally assumes that the user is a qualified and perhaps trained mechanic. They are almost never written specifically for the unqualified. I didn't mean to suggest that you were not, it was just a general statement about manuals. Some are better than others. Overall I find the aprilia manuals very good but they do not include step by step procedures. I used to own, drive, and work on MACK trucks. The manuals were the most comprehensive I have ever seen with thorough step by step procedures for just about everything.

Congrats on the A&P. I started studying for that back in the early eighties but dropped out after a few months due to other things going on in my life. Based on my own life long personal experience as a mechanic I can tell you that nothing teaches great mechanical skills better than a long life of working on all sorts of different machines and seeing a lot of different mechanics working on them.

There are only really three practical ways to locate TDC on these engines. Through the spark plug hole. Remove a valve cover. Or, unique to this engine, look through the hole for the crank lock tool while someone slowly turns the crank till you can se the slots.

Here is a picture showing the two notches you are trying to line up on.

Well, site won't let me upload a picture right now. Here is an image from the service manual that shows the slots. The cranks I have don't have slots as long as shown. They are not much longer than the diameter of the tool but should look about the same through the hole.

http://www.apriliaforum.com/forums/attachment.php?attachmentid=85884&d=1213737482

[resqav8r]

This helps clear it up thanks RZ; I was being lazy figuring nothing I'm swapping has to do with timing so I thought a TDC swag was good enough to put the bolt in to lock it up .. I thought it was ambitious to look for the exh & int allignment marks on the cam gear that show TDC plus I don’t have a valve cover gasket laying around in case it gets messed up when I pull the cover.

Guess I was hoping that someone could verify the shaft "key" at the 11 or 4 o clock position trick (if there is such a short cut). So I now that I see how it fits in there and with your explanation I see there is no lazy way to do it; again thanks you answer was just what I needed.

ALSO a note to the guy who did the swap and the starter now just spins .. check http://rsvzone.com/forums/showthread.php?6980-Sprag-which-one-and-where-do-I-get-one
which is where I read about the BMW part needing the lobes rotated because of engines turning direction (bmw vs aprilia).

The funny thing about the A+P was that when I did the school I was young and not aware of how pricey it is when you get it wrong ... now that I'm older I over think before I turn a wrench.

[kzmille]

Here is the photo I was trying to upload:

[resqav8r]

UPDATE: Okay this thread works real well. I just completed the job and here's my take away.
1.) TOOLS .. (A) the 100mm long TDC fix bolt works when insterted properly (thanks KZ) .. once you explained what I was looking at I did the cheater method (got it close to TDC by feel in top gear .. then looked in the hole while a friend rocked the wheel till the hole lined up). (B) The $15 (honda etc ) puller being sold by AF1 worked like a champ after I used a heat gun for about 5min (i think it was around 190deg F) only needed about 20ft/TQ to remove where before it was impossible with a breaker bar. (C) The handle I joked about was great during re-assembly as the stator magnets will suck the part back on and it's easy to damage the gasket.
2.) BEARING .. (A) I was not clear on which bearing I needed to got both the BMW 650 and 850 bearing .. and then I used the WRONG one. The 650 Bearing has a flange similar to the Aprilia bearing and the 850 Bearing dows not have a flat lip flange. (b) NOTE is that the 850 bearing worked like a champ after I flipped all the lobes (this must be done on either BMW bearing as ther engine rotates the opposite direction). (c) ALSO of NOTE is that the spring on both BMW bearings looks very SUSPECT .. I'll post a picture of the spring and the flange. 187751187752187753
3.) REASSEMBLY .. MY SPRING was no where to be found except maybe on all the magnetic parst. both the Gear and the star flange had wear marks so I planned on replacing both but AF1 sold me the wrong (3bolt) unit so I used my old slightly worn 6 bolt unit. Loctite 648 (very specific for rotating parts in high heat with high shear) was used in several places to hold it all together and Permetex RTV Black used in place of the Siltex.
4.) FINISHED .. Refilled new oil + filter, Let everything cure for about 6hours and bike started up within 1.5sec on the first crank. Will ride it for about 25miles to flush meta pits from old spring into new filter and change the oild again.

[hiss]

Have (nearly) finished my sprag replacement, have to add my +1 to the heat required. Waaaaaay more than I thought it'd need, but when I finally got it right I used one hand on a 300mm bar and it popped right off (nearly tried to catch the flywheel with the hand that didnt have a glove on it!).

Just gotta track down some 648 and buy some oil and we are back on the road - with tires, brake pads, and lots of carbon to get fitted :D :D

[Mick-e]

This thread was really helpful so I wanted to share my experience and slightly different method.

Thanks to DanV990 and the info in this post
http://www.apriliaforum.com/forums/showthread.php?155882-How-to-replace-your-sprag-clutch&p=2877174&viewfull=1#post2877174
I knew the puller was the same as a KLR.
With that info all I had to do was ping a few friends of mine, and sure enough I had the puller.
It seems every KLR owner has one.
With the bike in Neutral, and no other special tools I gave the rotor a little heat, and used my 3/4" air powered Impact gun, and the flywheel came right off.
110 PSI and a couple of pulls of the trigger and it almost fell on me.
No $32 bolt with a wing nut to hold the crank in place or other contraptions.
Installation is the reverse.
This is how I've pulled the rotors off many bikes and I've never had a problem.
I know this method isn't for everyone. Not that many people have air compressors in their garage, or a 3/4" drive impact gun, but if you do then you don't really need much else.
Some people might flame me for this as it's not the "correct method". If you're the type that needs to torque every fastener to the exact torque spec then this method isn't for you.

Thanks again to the OP, and all the contributors to this thread.
-mickey

[slowrider]

grrrrr my 05 tuono is starting to "clang" imediately after startup or at shutdown and i suspect the sprag clutch.
Im looking at what i need for parts,i want to have everything i need before i tear into it.
I know i need the sprag clutch gear----->http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=2839
Will i need this as well $377 ouch?---->http://www.af1racing.com/store/Scripts/prodView.asp?idProduct=2838
Thanks to all the people posting pics ect. i wouldn't consider doing the job without this forum
cheers

[kzmille]

You don't necessarily need the gear or housing but you definitely need the sprag clutch which is the expensive one. It is sometimes better to tear down and inspect before ordering so you can inspect the gear and housing and decide if they must be replaced. There are cheaper alternatives for the sprag clutch posted elsewhere in this thread.

[slowrider]

You don't necessarily need the gear or housing but you definitely need the sprag clutch which is the expensive one. It is sometimes better to tear down and inspect before ordering so you can inspect the gear and housing and decide if they must be replaced. There are cheaper alternatives for the sprag clutch posted elsewhere in this thread.
Thanks for the input kzmille i appreciate it.im gonna take your advise and start tearing it down and inspect each part and order as i go seems like it would keep the cost down.From what i've read i can go with the ducati sprag or the ktm?
Thanks again!

[slowrider]

Update!
i have a quik question im getting ready to pull the flywheel off (just waiting for the aprilia fly wheel puller and crank locker tool).Im following along with the instructions i see three allen head bolts that go into flywheel.If im reading correctly these just need to be loosened before i attempt pulling the flywheel off.Not taken all the way out?Is this correct
Thanks for the help!

[DanV990]

Update!
i have a quik question im getting ready to pull the flywheel off (just waiting for the aprilia fly wheel puller and crank locker tool).Im following along with the instructions i see three allen head bolts that go into flywheel.If im reading correctly these just need to be loosened before i attempt pulling the flywheel off.Not taken all the way out?Is this correct
Thanks for the help!

Those are the three sprag housing bolts. It is easier to loosen them before you remove the flywheel. If you know for certain that you were not replacing the sprag housing you could leave them alone and not bother loosening them. The sprag housing will come off with the flywheel. They should be loctited with 648 and may need considerable heat to remove. Mine were not loctited from the factory and were already loose (one had sheared off and ruined my stator too).

[slowrider]

Those are the three sprag housing bolts. It is easier to loosen them before you remove the flywheel. If you know for certain that you were not replacing the sprag housing you could leave them alone and not bother loosening them. The sprag housing will come off with the flywheel. They should be loctited with 648 and may need considerable heat to remove. Mine were not loctited from the factory and were already loose (one had sheared off and ruined my stator too).

Thanks dan for the help!
I'll try to loosen them if they dont budge ill get out the torch
Thanks again!

[fst.corner]

hi,
i have recently changed my sprag clutch (with the help of this topic) but i used loctite 270 instead of 648 (because it was sunday and thought i had )
but now i am very nervous should i be?
as i have read loct 270 is is designed for the permanent locking and
sealing of threaded fasteners. The product cures when
confined in the absence of air between close fitting metal
surfaces and prevents loosening and leakage from shock and
vibration. Typical applications include the locking and sealing
of large bolts and studs (M25 and larger).

thx makis

[go_modem_go]

Wrong Loctite.

270 is only for use on bolts & studs OUTSIDE the engine (engine bolts etc.), and not in a hot oil environment inside the engine, with the high temperature proofness, oil bath resistance and tensile sheer strength of Loctite 648! 648 can be used for bearing journals inside engines, 270 can't.

There is a good reason why Henkel Loctite 648 is up to twice the price than the "cheapo" 270... ;)

I wouldn't have used it just to get finished quicker, you'll always have a bad feeling in the back of your mind. Rightly so... :D

[fst.corner]

you are probably right.
but now what uninstall and reinstall it again with loct 648 or let it as is?
i mean the possibilities to go wrong

[DanV990]

you are probably right.
but now what uninstall and reinstall it again with loct 648 or let it as is?
i mean the possibilities to go wrong

http://i769.photobucket.com/albums/xx336/Kragges/Aprilia/IMG_0158.jpg

This is what happens when one of the sprag housing bolts that is supposed to have 648 on it becomes loose while the engine is cranking over and just starting up. Do you really want to take the chance of one coming loose at speed? Granted the chance is probably small, heck it took 26,000 miles for mine to loosen up and mine were never loctited from the factory (early production issue on bikes made before 2000 that I wish I had known about before it broke), but I can only imagine the damage one of those bolts would do if it broke loose at 9,000 RPM. Personally if I were you, if for nothing else than the peace of mind, I would go back in there and replace it with the correct loctite. That alone in my opinion is well worth the cost of a bottle of 648 and a couple of hours wrenching on your bike.

[kzmille]

This is the result of no locking compound at all rather than using the wrong kind. I would be less worried about 242 on the sprag housing bolts and more worried about it being used on the crank taper and flywheel retaining bolt. Before Loctite developed 243 oil resistant compound 242 was in common use inside engines for all medium strength locking needs. It was used internally for decades by everyone. The only reason that it is suspect at all for internal use is because Loctite brought us oil resistant 243. 242 is probably adequate for the flywheel retaining bolt as well.

The real concern here is the crank taper. The engineers specify 648 and I trust their judgement here. 242 would be nearly useless on a taper.

I would redo everything with the correct 648.

[fst.corner]

thanks for your replies and your interest,i understand the difference between 2 glues and the side of damage if something go wrong:crybaby:

[Db71]

I just did my sprag a few weeks ago. Big thanks to all on this thread. I went with the OEM housing, and a BMW sprag, works like brand new.

After comparing the worn vs. new parts, I feel that the sprag was probably ok, it was the housing that was worn out, definite grooves worn into it.

My biggest pain was getting the stubborn flywheel off. I bought the 22mm bolt, and tried pulling it off after heating it, all I did was mangle the threads. I used my oxy-acetylene torch, and started heating it just til it started turning color, and it fell off on it's own.

Bike runs awesome now.

What was the part number for the BMW sprag? I am fixing to do this on my sons bike and may have trouble finding parts. First stop is Micah. Then wherever I can get em if he doesn't have em

[DanV990]

What was the part number for the BMW sprag? I am fixing to do this on my sons bike and may have trouble finding parts. First stop is Micah. Then wherever I can get em if he doesn't have em


Ducati 70140071A
BMW ENA57177
KTM 58440026000

Both the BMW and the KTM parts need to be either installed backwards or have their sprag lobes reversed.

I put a KTM freewheel 58440026000 in my bike at 26,000 miles and just installed it backwards. It is still going strong at over 54,000 miles.
The KTM is the least expensive of the three alternative sprag clutches. I bought mine at ktmworld.com for $80 . The OEM Aprilia part costs over $370 so the savings is almost two hundred dollars.

[DanV990]

http://www.ktmworld.com/products/1422-free-wheel-fwd-33200.aspx

[Robert Borchert]

Thanks for the link! The OEM one is made of unobtanium, hand massaged by Swedish maidens, and comes with a framed certificate of authenticity.

Well, there sure seem to be enough original ones that have grenaded gloriously, so that should be testament enough, shouldn't it?

I'll be sure to file a Form 337 after installing a replacement. Mine's been chugging along nicely, but you know how that goes...

Bob

[ghostrider71]

I ordered my KTM Sprag from KTMWorld this week. Looking fwd to FINALLY doing this after 5 years of worrying abt it!

Question for the knowledgeable:
I have access to DYNATEX Thread locker in Medium GREEN and RED applications.
A quick look at the MSDS sheets reveals the RED to be 3000psi sheer compliant, with the GREEN to 2000psi.
Both have an operating temp to 300 degf.
The RED is more applicable to internal engine components, and applications where "future disassembly is improbable".

Given this limited info, i'm favoring the RED.

anybody have any thoughts?
I can post the MSDS sheets if it'll help.

thks.

*I'm sensing that KZ will find this one IRResistable!* :D

[kzmille]

Yeah, that's easy. Use the specified 648 from Loctite.

[Robert Borchert]

kzmille is right, the simplest thing to do is run the specified locking fluid, Loctite 648, as recommended by Rotax and Aprilia.

Playing devil's advocate, I looked at the choice juices available in the workshop. We gots them there red and blue lockin' tites, a whole handful of silicone adhesives, but 648 is a rarity in the USA. Go figger.

The sprag clutch and rotor aren't "unlikely to be disassembled", it looks like the darn thing should be velcroed in place, as often as they go ka-boing. All joking aside, AF1 has the juice du jour available at an acceptable price, and the 648 releases readily when heated, as it's supposed to.

I have some VW AG preparation here, two bottles of Sicherungsmittel D 000 600 A2, looks like 648, smells like it, and it costs over $60 a bottle too, but God only knows what the Loctite equivalent of this stuff is. I'm just going to pick up some 648 to be sure.

Bob

[go_modem_go]

Robert,

Is your VW Sicherungsmittel D 000 600 A2 liquid green or red?

If the liquid is green (not the bottle!), its made by Febi-Bilstein - hochfest (very tight), and used for screws on the engine.

http://abload.de/img/d-000-600-a2-4651czuoc.jpg

€37.- at Volkswagen/Audi or Seat / Skoda spare depts. They really seem to rip off VW AG customers, especially in the US.

The same bottle by Febi-Bilstein themselves is a mere €7,81 ($10.-) over here in the Fatherland! Expensive enough... :D

http://p2gs.de/images/product_images/original_images/101/26709.jpg

Imo, you can use your Volkswagen / Febi bond. It's similar to 648 (150°C heat and oil strength, used up to 175°C, >250°C will loosen the bond for disassembly).

PS: Weirdly enough Henkel-Loctite 648 seems very common over here in Europe, every DIY store carries it. Never had any trouble sourcing it.

Both bonds need approximately 10-24 hours to reach full bonding strength on Aluminium - less time on steel.

[Robert Borchert]

Yep, that's the stuff. Red bottle, green fluid. Funny thing, it looks exactly like the same bottle as Loctite uses. I have some of the anaerobic sealant, the orange gel, in the quirky "accordion" style bottle, somewhere around here. I see a similar bottle depicted in the chemicals page in the workshop manual. That's a loctite product as well.

Finding the specifications for these products is a real pain, as they're OEM rebranded.

Bob

[DanV990]

Funny thing, it looks exactly like the same bottle as Loctite uses.

Looks different than the bottle of 648 Loctite that I have.
http://i769.photobucket.com/albums/xx336/Kragges/BBEBA4FA-38EF-4F9C-89B4-CCB6EA2A5622-2275-0000019A82CC897A_zps8d095589.jpg

[deefred]

They come in several different sizes and the 5ml is the smallest and differently shaped.

[MCL]

Just wanted to post a little warning regarding the original poster,who btw has made a very nice how to article.Be very careful heating the flywheel with a torch,the magnets will loose their magnetism if heated up enough rendering it useless.

A safer method would be to install the puller,apply a good amount of torque(not so much that any thread will strip/parts will break,and then tap the flywheel on the sides with a rubber mallet.Just pound it for a while,if your short on tools you can use a hammer and use wood as a middle part.

I usually start with only little torque on the puller,pound it a bit and if it doesnt loosen i increase the torque and try again.This has never failed me and never really needed much torque on the puller anyway.

Whats the symptoms of a sprag going bad?Thing is my bike starts and stops silently with no noise,but every so often I release the starter button too soon as I hear it cough and it doesnt start which results in a quite loud mechanical noise like hitting a hammer on metal.Would this be a symptom of a sprag going bad?Otherwise its completely silent.
Sounds very much like in this video:
http://www.youtube.com/watch?v=xr2Dv2r_sA0
If I adjust the idle way low and try to start the bike when its cold it obviously wont even try to come to life,but there is no sprag noise since the engine doesnt even try to start,it just turns over with normal starting noise.I only get the noise if it fails to start because i release the start button too soon.

[kzmille]

...Whats the symptoms of a sprag going bad?Thing is my bike starts and stops silently with no noise,but every so often I release the starter button too soon as I hear it cough and it doesnt start which results in a quite loud mechanical noise like hitting a hammer on metal. Would this be a symptom of a sprag going bad? Otherwise its completely silent....

No, what's happening is sometimes on a failed start attempt one piston is coming up on compression and when it fails to go over TDC it is forced back down turning the crank backwards. This engages the sprag and turns the starter backwards, often with a loud sound. Obviously you want to minimize this but in and of itself it is not a sign of sprag problems.

On the torch thing, the heat should be directed at the center hub only and the heat is not likely enough to damage the magnets.

[auditude]

So how does one get the starter to spin back in the correct direction? Mine is just spinning and spinning and has never given an indication that he sprag was failing.

[kzmille]

Push the starter button.

If it's just spinning and the engine is not turning that is a pretty strong indication that the sprag is shot.

[auditude]

Push the starter button.

If it's just spinning and the engine is not turning that is a pretty strong indication that the sprag is shot.


I was afraid of that...I was hoping a simple fix but it doesn't seem in the cards for me.

I'm curious to know - there was no prior warning of failure. This was the first time ever hearing the whirring of the starter without engaging. Is there a procedure to prevent failure in the future or is the sprag assembly destined for doom regardless? I would think there must be some other form of prevention to prolong the life of the sprag assembly or must an owner of the famous Rotax engine invest in a flywheel puller and all associated parts in preparation of evident future failures?

I'm at just over 6 weeks of ownership with less than 250 miles of ride time and have been riddled with problems and gremlins. I am seriously rethinking my purchase. At this point I'm underwater on the buy in both time and money. If I were to try and sell her I'd lose nearly half of my investment thus far and clearly all my time (this is without replacing the sprag) and if I were to fix her, as if I weren't already, I'm married to the bike for eternity because it will be a very long time before the value of the bike will ever catch up with how much time and money I've "dumped" in to her up to this point.

Sorry, just venting and ranting but very frustrated at being stranded twice in some rather fortunate locations (once at a shop and the other within reasonable distance to a shop that was able to trailer me to their garage).

[kzmille]

Keep a healthy battery in the bike and minimize starting as much as possible but otherwise there is not much you can do to preserve it. I've never had to replace mine. 11 years and over 20,000 miles. Many others have done much more. You can get a decent puller for $15. (http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=1634)