Valve Clearance Adjustment

[CessnaTPA]

I thought I'd share with everyone how I adjusted one of my intake valves. The only specialty tools you would need is the timing pin 020719Y which you can get from AF1 Racing.




After taking off the head cover take the crankshaft to top dead center rotating the rear tire in 6th gear (Tip: put it in 6th gear the night before, much easier with engine running) note the position of the cam lobes.(for front cylinder only)
Then install the timing pin through the camshaft in the opposite side you will be adjusting, the pin pushed in about 2 1/8", I had to rotate the motor a little to find that sweet spot to get the pin to drop in. Yellow arrow pointing at timing pin.



I marked the gears with white out so there would be no mistakes reinstalling the cam shaft.



Remove the 8 bolts holding the cam cap and carefully lift the cam cap out without disturbing anything.
View with cam cap removed.




The cam shaft lifts easily out.



Remove the bowl tappet with a magnet to reveal the timing shim.



View of timing shim removed.



Bowl tappet and timing shim.



Then do the math on what size shim you need and reverse the order to reinstall and be 100% sure you install the camshaft in the same groove.
The cam cap does need to be pre tightened to 4.90-6.86 Nm in this sequence then to 9.81-12.75 Nm, I also prelubed all the moving parts with motor oil and used Permatex Motoseal on the head cover.

[petemoss]

Excellent! glad to see the rest of the process completed.

for the timing pin tool, is there anything special about its shape on the end, or is it just a long pin? what is the diameter?

[JetdocX]

Thanks for the great pix, Cessna. I have the timing pin from the PO, but wouldn't a drill bit accomplish the same task????

Edit: Wow! No silly chain to fool with when removing the cams???? I'm liking this engine a lot. I'll probably doing this this winter for the 12K.

[CessnaTPA]

Excellent! glad to see the rest of the process completed.

for the timing pin tool, is there anything special about its shape on the end, or is it just a long pin? what is the diameter?

It's about 3/16" but I know it's metric

[vfr_nz]

Hi

Any chance of measureing the diameter of the pin with a micrometer?

Thanks

Wayne
In New Zealand

[keithc]

Well done for this post. I have just looked for the last very detailed post on gaining acces to the valves and cant find it. And yes I have treid the search function and have also looked back and cant find it anywhere.
If anyone could find it and post a link I would appriciate it.

Keith C

[DownUnderDorso]

Nice write up !

At how many miles did you identify that you needed to adjust the valve clearances ? Could you feel (or hear) that the clearances were outside of recommended spec ??

[CessnaTPA]

Nice write up !

At how many miles did you identify that you needed to adjust the valve clearances ? Could you feel (or hear) that the clearances were outside of recommended spec ??

I checked the valve clearances at the 625 mile service (641 to be exact) and the results were

Front Intake Left .003" Right .005
Exhaust= .007 .008

Rear cylinder .005 .005
.007 .006

Intake needs to be .0043- .0071"
Exhaust .0063- .0091

So the front left intake was a thousands of a inch too tight and as the engine wears it could get worse. After the new shim it's .005", the bike sounds and rides the same. Could I of got away without doing it? Probably, but I didn't want to take the chance. Call me crazy but I wanted to tear it all apart and see what was inside. I get a satisfaction out of doing things myself, not to mention all the $$ I saved

[Guyf]

Very nice and useful write up, thanks!

[Strada_Stu]

I have just looked for the last very detailed post on gaining acces to the valves and cant find it.
If anyone could find it and post a link I would appriciate it.

Keith C

http://www.apriliaforum.com/forums/s...alve+clearance

[Ed / AF1 Racing]

it needs to be stressed again that you only take ONE camshaft out at a time.

Being a 90 degree engine, the cylinder you are not working on is under valve spring tension.....pull the cams, and the crank will roll, and you loose your timing. Setting the timing from scratch on these engines is a very complicated project, and reruires several more special tools. DO NOT LOOSE THE TIMING.

One cam/cylinder at a time, and lock the other cam in that cylinder while service the one cam.

[keithc]

http://www.apriliaforum.com/forums/s...alve+clearance

Thanks mate

Keith C

[iancp5]

it needs to be stressed again that you only take ONE camshaft out at a time.

Being a 90 degree engine, the cylinder you are not working on is under valve spring tension.....pull the cams, and the crank will roll, and you loose your timing. Setting the timing from scratch on these engines is a very complicated project, and reruires several more special tools. DO NOT LOOSE THE TIMING.

One cam/cylinder at a time, and lock the other cam in that cylinder while service the one cam.

You can't lock the crank easily then? Some KTM dirtbikes had a bolt with a thick washer on the crankcase. You removed the washer and screwed it in when the crank was lined up and it located in a hole in the crankshaft thus locking it. Good idea I thought. Of course that was on a bike that didn't need it for valve clearance adjusting!

[CessnaTPA]

Hi

Any chance of measureing the diameter of the pin with a micrometer?

Thanks

Wayne
In New Zealand

The diameter is 4MM and 100MM long.

[maddad]

all of what ED said,done all of my in-line 4s,easy re timing on the old kwaks,this ones going to the shop the $ are nothing compared to spanner throwing and inevitable trailering to the shop,as for the engine wearing later down the track it may go one way or the other,talked to a sevice guy here a little while ago and a shiver at 20,000ks needed no adjustment.