View Full Version : Preservation Project

06-09-2015, 10:42 AM
I've decided to start a project thread so I can document the things I do to my bike. It's a 2000 Aprilia RS50 in Rossi colors. I picked it up in August 2013 from the 2nd owner with just 517 original miles on the odometer. The first owner was reportedly an Italian bike collector who had all the mods done when new and then used it sparingly. The second owner bought it sometime in 2012 or 2013 and added a few more miles but he also had other Italian bikes to enjoy and it wasn't getting much use.

I'd always wanted a RS50 from the moment Aprilia first came to the USA in the late 1990s. I was in college at the time and desperately wanted the RS50 as a campus runabout to get back and forth to classes. Unfortunately, I was working just to pay for tuition and living expenses and I'd have to make do with a hand me down bicycle. I graduated and started my career and saved up enough money to buy a car and started racing that instead. ~10 years go by and one day I am reunited with my Aprilia obsession when I see a young fellow riding his RS50 away from the train station. Instantly I was transported back in time to a place where all I could dream about was this cool little bike. When I got home I hopped on the Internet to see if any were for sale. I knew they were rare bikes here in the USA but as luck would have it I found one listed on eBay and it was just 15 miles away from me! Talk about serendipity! Long story short, the seller and I worked out a good deal for both parties. He rode the bike over to my house, I gave him the cash and a lift back to his house. It came with some spare spark plugs and injector oil. Weeee!!!!!!!!

http://farm4.staticflickr.com/3692/9615808532_c4f28665e6_b.jpg (http://www.flickr.com/photos/addlightness/9615808532/)

http://farm8.staticflickr.com/7409/9615807260_ce51a87b46_b.jpg (http://www.flickr.com/photos/addlightness/9615807260/)

http://farm6.staticflickr.com/5522/9615796806_dbaf95e1cf_b.jpg (http://www.flickr.com/photos/addlightness/9615796806/)

http://farm4.staticflickr.com/3721/9615800042_59833a3664_b.jpg (http://www.flickr.com/photos/addlightness/9615800042/)

http://farm3.staticflickr.com/2805/9612554709_fa29f92d78_b.jpg (http://www.flickr.com/photos/addlightness/9612554709/)

http://farm8.staticflickr.com/7344/9615795744_695f159302_b.jpg (http://www.flickr.com/photos/addlightness/9615795744/)

http://farm8.staticflickr.com/7343/9615785786_6f0a13c8d7_b.jpg (http://www.flickr.com/photos/addlightness/9615785786/)

http://farm6.staticflickr.com/5456/9616849342_0476eae386_b.jpg (http://www.flickr.com/photos/addlightness/9616849342/)



My goals are to keep this bike as nice as possible while still enjoying it occasionally on nice days. I don't care to ride on the street much as I find it too dangerous and the limited power of the RS50 actually exacerbates the problem. So I'll probably just cruise around my quiet neighborhood to disturb the peace and kill a few mosquitos and take it out early weekend mornings to the local car and bike gatherings nearby. That's about it. The bike isn't stock but it has all the period correct mods that make it way more usable for a man of my size. The first two owners did a good job of preserving the bike and I feel it is now my responsibility to keep up that effort.

06-09-2015, 01:12 PM
Mods from stock are pretty standard for a USA bike:

Top Peformance "Pink" Racing (TP75) Cylinder Kit
Arrow race expansion chamber with carbon fiber silencer
Mikuni TM24 flat slide carburetor
Uni foam air filter
TCM rearset footpegs
Galfer braided steel brake hoses
Sprocket Specialists 43t aluminum rear sprocket
Choke cable conversion
Rear fender eliminator
Aftermarket turn signals

06-09-2015, 01:31 PM
The first thing I did when I got the bike was to repair the turn signals. A previous owner had replaced the OEM turn signals with generic aftermarket units and they weren't working. I suspected the flasher relay was bad but I wasn't sure if I had LED turn signals or not. So instead of trying to source an OEM replacement flasher that may or may not work with my aftermarket turn signals, I went with an aftermarket flasher unit from a reputable vendor who guaranteed it would work with a wide variety of turn signals. Success! Turn signal function restored.

https://c2.staticflickr.com/6/5546/9655530241_b10028c89b_b.jpg (https://flic.kr/p/fHe7Kk)
Aprilia RS50 flasher relay p/n AP8124235 (https://flic.kr/p/fHe7Kk)

CF12ANL-01 LED Flasher

06-09-2015, 01:35 PM
Next I purchased an OEM Aprilia Indoor Bike Cover (p/n 854611) to keep dust off my pride and joy.

https://c4.staticflickr.com/8/7363/9875116206_1d9bd25cd8_b.jpg (https://flic.kr/p/g3Cy1f)
Aprilia cover right (https://flic.kr/p/g3Cy1f)

https://c2.staticflickr.com/6/5522/9875088495_2df9f65362_b.jpg (https://flic.kr/p/g3CpLt)
Aprilia cover left (https://flic.kr/p/g3CpLt)

06-09-2015, 01:46 PM
After riding it around a bit I discovered a rather substantial oil leak at the cylinder head exhaust port.

https://c4.staticflickr.com/4/3770/10838541656_1d3f79f31d_b.jpg (https://flic.kr/p/hvLmPS)
Exhaust Port Oil Leak Side View (https://flic.kr/p/hvLmPS)

https://c4.staticflickr.com/4/3818/10838612826_fc07d5f65f_b.jpg (https://flic.kr/p/hvLHYW)
Exhaust Port Oil Leak Top View (https://flic.kr/p/hvLHYW)

Turns out the exhaust o-ring was completely missing. I didn't know whether the OEM exhaust o-ring would work for me since I have an aftermarket cylinder kit and exhaust pipe. The OEM parts list on AF1 shows two exhaust pipe o-rings: D25x2.6 (AP8206976) and D28.2x2.6 (AP8502668). I was told that the 28mm was the one I needed. But still being uncertain I did some measuring and I ordered a few different sizes (28mm x 2.5mm, 121, 122) of Viton o-rings from an industrial supplier. Viton o-ring size 122 (ID 1 1/8", OD 1 5/16", width 3/32") seemed to fit best and cured my oil leak. Then I cleaned up the motor a bit.

https://c4.staticflickr.com/4/3768/10839902986_9db6d7f979_b.jpg (https://flic.kr/p/hvTkv5)
Engine Right Side View 1 (https://flic.kr/p/hvTkv5)

https://c4.staticflickr.com/4/3737/10840179603_68b1b38a0c_b.jpg (https://flic.kr/p/hvUKJk)
Engine Right Side View 2 (https://flic.kr/p/hvUKJk)

https://c4.staticflickr.com/4/3811/10839843265_0dd6a7695f_b.jpg (https://flic.kr/p/hvT2Kp)
Engine Top View (https://flic.kr/p/hvT2Kp)

06-09-2015, 01:49 PM
Nice RS.

It's a tough choice really. Preserve it, or thrash it. On the one hand, getting a good original RS50 is tough (As they get thrashed and neglected by 16'ers). So preserving it is a good thing. The bike also keeps its value. On the other hand, the RS50 is meant to be thrashed. The good thing here is that you're not a 16'er, so neglect won't be a problem. I'm sure that you'll find a happy balance between the two mind sets.

06-09-2015, 01:50 PM
Around this time I started collecting literature on Aprilia motorcycles. I bought a few books, collected the parts manual, engine repair manual, workshop manual, use/maintenance, etc. I'm still collecting the Aprilia Racing Annual books if anyone has any for sale or knows where I might find them. So far I have collected 1999, 2001, 2004 and 2006/2007. I am still looking to find years 2000, 2002, 2003, 2005 and anything pre-2000 if any exist.

https://c1.staticflickr.com/3/2832/9778882152_a2cd998e66_b.jpg (https://flic.kr/p/fU8jYq)
Aprilia books (https://flic.kr/p/fU8jYq)

06-09-2015, 01:53 PM
Nice RS.

It's a tough choice really. Preserve it, or thrash it. On the one hand, getting a good original RS50 is tough (As they get thrashed and neglected by 16'ers). So preserving it is a good thing. The bike also keeps its value. On the other hand, the RS50 is meant to be thrashed. The good thing here is that you're not a 16'er, so neglect won't be a problem. I'm sure that you'll find a happy balance between the two mind sets.

Thanks! My plan is to keep this bike nice and then pick up another RS50 that's not quite as pristine so I can do all the cool stuff I want to it. I just have to decide whether to do a proper 50cc Am6 build with rotary disc valve conversion, etc. so I can race it in 50cc series or decide whether I should stuff a CR125 motor in there like mattology!

06-09-2015, 02:11 PM
The choke plunger (or rather the cold start enrichment circuit plunger) on the aftermarket carburetor was really hard to reach with gloved hand. So I decided to convert the choke to cable actuation using a combination of Aprilia and Mikuni parts. To keep things nice and tidy I purchased a new LH switch assembly w/ choke lever (AP8224413) and the choke cable (AP8214219) as used on certain Aprilia RS50 SE-TS models and some RXV / SXV 450 bikes. This control is nearly identical to the original LH switch fitted to AM-USA models (p/n AP8212986) with the following differences:

1) The flash to pass button is blue instead of gray.
2) It uses two different length Phillips head screws to clamp the two halves together. These screws are larger in diameter than the equal length socket head cap screws used on AP8212986.
3) Choke lever and choke graphic.

Interestingly, the original switch (AP8212986) has the threaded hole to accept a choke cable but uses a dummy choke lever inside the switch and lacks the choke graphic. If only the little lever part was available separately I could have saved a bunch of money! That being said, it was worth the wait to get the parts from England to save over 50%.

https://c2.staticflickr.com/6/5331/9778860141_675a95857e_b.jpg (https://flic.kr/p/fU8dqV)
Mikuni cable choke conversion parts (https://flic.kr/p/fU8dqV)

https://c2.staticflickr.com/6/5473/10840182143_d28383e335_b.jpg (https://flic.kr/p/hvULu8)
Mikuni cable choke conversion specific part numbers in MK-412 kit (https://flic.kr/p/hvULu8)

https://c4.staticflickr.com/8/7380/10910988066_607298f7f8_b.jpg (https://flic.kr/p/hCaEBU)
Choke Lever Off (https://flic.kr/p/hCaEBU)

This whole excercise also gave me the opportunity to learn how the TM24 works and what settings it had.

Needle Clip Position 3
Jet Needle 5N13
Throttle Valve 832-30006 #3.0
Needle Jet 454 Series #Q-0
Pilot Jet VM22/210 #15
Air Jet Fixed
Air Screw Two turns out
Idle Screw Approximately 1,400 rpm
Main Jet 4/042 #210
Float Height 23mm

Update: after living with this cable choke for 1 year, I'm not 100% happy with the way the bike starts when cold. It seems the choke is having little effect so I'm not sure whether it is the cable actuation itself or the carburetor internals that need to be addressed. There was initially some confusion as to exactly which Mikuni parts were needed to do the conversion with some suppliers saying one thing and other saying something else. Allens Performance actually lists two different kits for the TM24-9 carb, the MEG-034 and the MEG-036, that utilize different part numbers for piston plunger, spring, etc. So I'm going to do some experimenting to see if I can't improve cold start function.

06-09-2015, 02:24 PM
I rode the bike to the local "Bikes and Breakfast (http://www.bikesandbreakfast.com/va-photos.html)" gathering where my "weedwacker with tires" was well received.
https://c4.staticflickr.com/4/3910/15064310388_6dd920da3a_b.jpg (https://flic.kr/p/oXbwDs)
rs50 (https://flic.kr/p/oXbwDs)

I rode the bike when I was furloughed for a couple of weeks back in 2013.
https://c4.staticflickr.com/4/3685/10247622794_636b2c7132_b.jpg (https://flic.kr/p/gBxKeC)
RS50 ride on first day of furlough (https://flic.kr/p/gBxKeC)

I parked the bike in my 1 car garage/workshop next to the other project bike, a Honda CB350 vintage racer.
https://c2.staticflickr.com/6/5322/9613688855_7a9de54687_b.jpg (https://flic.kr/p/fDwEL8)
Together in garage (https://flic.kr/p/fDwEL8)

I rode the bike from the old townhouse over to the new single family detached house one day in February when the roads were clear and it wasn't snowing.
https://c1.staticflickr.com/1/330/18651398961_bf6307e517_b.jpg (https://flic.kr/p/uqai7a)
Bikes in new garage (https://flic.kr/p/uqai7a)

06-09-2015, 02:28 PM
Package from Treatland (http://treatland.tv/) arrived. They're the coolest scooter shop around. Got some new Sava MC18 tires, 17x90/80 front, 17x110/80 rear to replace the 15 year old original equipment Pirelli MT75s. These Savas are supposedly the bees knees for street tires in the original Aprilia RS50 sizes. I know Sava is a brand name owned by Goodyear EMEA but I'm not sure if Goodyear owns the motorcycle tire side of the business also. Sava motorcycle tires (http://www.savatech.eu/tyres/motorcycle-tyres.html) are made in Slovenia. Their race tires are used in many motox, enduro, scooter, minimoto and pre-GP racing series across Europe.

Got the bike up on stands so I could remove the wheels and change the tires using good old fashioned tire irons. This required leaning the race bike against the wall since it has no onboard stands, converting the rear stand from spool lift to paddle lift, and converting the front stand from headlift (under lower triple tree) to fork lift. I really need to get a spare Forklift Converter with a different size pin so I can more easily swap the stand between bikes. Sadly, there is no easy way to convert the Aprilia swingarm to spool lift.
https://c1.staticflickr.com/1/543/18397642590_3d3421b22c_b.jpg (https://flic.kr/p/u2JJbj)
Aprilia up on stands (https://flic.kr/p/u2JJbj)

Decided to clean up all the grime that had accumulated on the wheels and give them a fresh coat of carnuba wax.
https://c1.staticflickr.com/1/307/18618639682_f3e7d1baf6_b.jpg (https://flic.kr/p/ungoV1)
Rear wheel all cleaned up brake side (https://flic.kr/p/ungoV1)

I need to check the countershaft sprocket to see if it's the original 12t sprocket or an aftermarket one. The rear sprocket was changed from stock 47t to aftermarket 43t.
https://c1.staticflickr.com/9/8862/18435534770_9091a47228_b.jpg (https://flic.kr/p/u65WcL)
Sprocket Specialists 43 tooth rear sprocket (https://flic.kr/p/u65WcL)

Everything's all put back together. Time to go scrub these new tires in.

06-09-2015, 02:33 PM
Just a couple of comments.

Considering that you've got the very popular Top Performances pink kit. A larger carburettor. A better exhaust, etc, etc. A certain aspect of preservation has just gone out of the window. I take it you still have the original parts?

I've got the 1999 model. That didn't have the handlebar choke lever either. Sadly, buying in a seperate lever isn't an option. The cluster mouldings are slightly different. The lever doesn't fit. If you want the totally original look, then you'll want to get the parts from an RS125. That's what I bought. I also bought the left hand handlebar cluster as it had a kill switch on it.

06-18-2015, 05:14 PM
A certain aspect of preservation has just gone out of the window. I take it you still have the original parts?
I hear what you're saying. I suppose I'm preserving it the way it was circa 2000 (more or less) and the way many in the USA were immediately outfitted after leaving the dealer showroom so they could actually be used by grown adults on US roads. Standard RS50s are much too wimpy and I don't think anyone really wants a completely stock one today except for maybe someone who only plans to show it off in an Aprilia museum and not actually ever ride it. So while my bike is not factory original it is absolutely period correct. In fact, I wish I could get some of the cool tuning parts from that era that were rare when new and unobtanium today like the Acculign adjustable triple trees.

06-20-2015, 05:48 AM
I can see where you're coming from.

It's a case of the same word having slightly different meanings, dependent on where you live. In your case. The expression I'd use is: Period restoration. In other words; You're restoring a bike with parts that were only available in a given time period.

06-20-2015, 07:46 AM
Not much restoration needed on a bike with ~600 miles on the odometer that's been garaged its entire life. It mostly just needs some detailing and fine adjustment.

06-20-2015, 08:55 AM
i drilled and tapped my swing arm.....now i just have to get the correct stand


06-20-2015, 10:15 AM
That's the way I've seen it done also. Not sure I'm ready yet to take the plunge as it is a permanent mod but it sure would be nice to have the same setup as my other bike. It looks like you've also got the OEM Aprilia stand?

06-20-2015, 05:03 PM
no it's an after market front stand, but the rubber protective arms fit nicely under the swing arm