CR 500 questions

[Dodd]

I'm thinking about putting together a 500cc 2 stroke track bike this winter for track days and the occasional race this season out at HPR. Thinking this would be a cheap fun way to get back at it after a year or so of sitting on the bench.

I did some research and found a fella named Chuck Shettsline ran a CR 500 in 09, I remember seeing him out at Pueblo. If I remember correctly, I read in the fourms that he ran this bike for several years. Does anyone have contact info for him? I'd like to pick his brain.

And any other info from anyone that has experience with big 2 strokes and road tracks.

Thanks-
Dodd Jacobsen

[JohnGarc]

Go for it man.. I built a DT400 / CB350 hybrid... It was fun in the sun and was excellent handling for track duties.. Plus it was cheap and hella fun. Let me know if you need any help.

[jgixxer1]

Do it!! They are a lot of fun. I had one last year. Never did a race but several trackdays at PMI. I'm not by any means fast, but after riding a session on the cr500, then jumping on my zx6r for the next session, I was shaving seconds off my zx6r lap times. I think it made me a better rider much quicker. Unfortunately, I had to sell it but have been looking at another one. I thought mine was something special, but this one shits on my old one.

This one has full Ohlins!! You can't build a bike like this for what this guy is asking. $10,000 in the build and he only wants $3250!! And it has a title which is priceless. You can't even find a clean one in dirt trim for under $2k. This one has 3k in suspension 2k+ in wheels and brakes. Has motor work done and a $500 lighting coil. I think the bajadesigns coil puts out 180w. You can run some serious lighting with 180w. I checked with uship.com and you can have it shipped for about $375. Taxes are coming and I'm gunna get this bike or a Husaberg fs650 supermoto. Leaning more towards the Berg but can't decide. Jump on it before someone else does or before I do. I would love for an MRA guy to buy it so I could see it in person. Buy it so I don't have to fight with myself over the Berg or the CR. Here's a link.

http://forums.13x.com/showthread.php...ighlight=cr500

[Jim 'smooth' Brewer]

A good place for technical info (like parts diagrams & year swapping) check out http://cr500riders.com/

[Dodd]

Thanks for you guys input- I did see that CR in the WERA boards, but decided I'm going to build my own, trying to keep cost "Reasonable" by doing all my own work. Plus I have a 5 week old at home, so if I'm not at work, I'm here and needed something to do to keep from going bonkers.

I picked up a 1991 2 owner KX500 the other day from a guy out of the FC area. I was pleasantly surprised to see how good of shape it was for a 20 yo dirt bike. Straight frame, starts in 2 kicks with a healthy idle, etc.

I took it home and having never turned a wrench on a dirt bike, was able to get it to the frame in under 5 hours, with cataloging, documenting and sorting every stinkin' nut that came off it, so I can put it back together.

I took the frame, subframe and swing arm to the wash today to get the grime off, then its on to media blast it and then powder coat.

My plan is somewhat simple- 17" supermoto wheels, prob. some warp9's or a good used set of Excel's. A decent front brake, MC and some slicks. I want it to look clean and uncluttered, with no flashy paint or gadgets. All black plastics with a black frame. In the saving money front I'm going to keep the stock forks and shock, and I'll rebuild them w/ race tech type 1 valves, and some new springs. I've never done that either, so all of this is as much a learning experience as it is to make something to kill mosquito's out at HPR...

As for the motor, a solid re-build, new bearings and the such. I'm going to have the crank balanced to keep it from shaking itself to death, a good con rod and good piston and thats about it. Oh and a high rpm power pipe- used if I can find it. I can only get away with so much gearing, but I'm aware of that.

My initial questions- I could most likely get a 5 inch rear wheel in the swingarm, from what I've read which will allow me to run a 160 rear (And make take off's easier to come by) plus give a bigger contact patch. BUT I would have to shim the rear axle to the right and build some kind of chain deflector to keep the chain from eating the tire. I'm wondering if going with a 4 1/2 or 4 1/4 and I'm assuming a 150 will give me enough rear tire to keep the rubber side down-

Also for now- I live up in the frozen north (Grand County) and there is no place to get any media blasting done. Having the problem that I cant be running down to Denver every day off, I'm wondering if buying a media gun from like HF would be a worthy investment. I looked today, and I can get a mid-range gun for $120, and a bag of walnut shell powder shipped free for less than $150. I have access to big compressors to run it, so I don't know.

I thought about posting up pics as the build progresses, if anyone is interested. Also, who in the club can point me toward a good racer friendly powder coater?

Dodd

[ducati7044]

I've raced a cr500 for years. Chuck and I raced together many times. They are fun. I mainly race mine with AHRMA. However last year I raced the last race of the mra season at HPR. Even with a cold seized motor I still did well! Mine has been highly modified over the years. 70+ rear wheel HP
16 tooth front sprocket, ported, pipe, 10 map vortex ignition, etc. etc. If they're built right the motors are pretty bullet proof.

[Dodd]

Great! I'm looking forward to it. Should be a hoot. I remember seeing Chuck blasting around on his CR and thinking that looks like fun-

Dodd

[jgixxer1]

With what you want to do to the bike, plus the cost of the bike, sounds like you'll have about $3k in it easy by the time you're done with it; when there is a bike ready to go with ohlins and built motor for that much. You will be more proud of the bike though knowing that you built it yourself.

As far as running a 5" rear wheel, no need to shim rear axle or get custom spacers made. Just fit it up and offset the rim by loosening sprocket side spokes a 1/4 turn, then tightening rotor side spokes 1/4 turn until you get desired offset. And you can also use washers to shim the front and rear sprockets. Or flip the front sprocket. I don't know what the kx500 one looks like but I just flipped the front and shimmed the back on my cr.

I would go with the 5" rear if I was gonna do it again. I had 4.25" warp9 on mine and ran a michelin power one 150/60 and I couldn't get rid of the chicken strips at the track. About a 1/4". When I would go past that the rear end would step out due to the profile being too pinched on that rim. Other tires may be different. 4.5" rear would have been perfect for the power one,150/60.

[Dodd]

Good info. Yes I plan on running Michelin slicks- and or what ever take offs I can get from fellas or gals running 160's. Great thanks guys, I'm getting really pumped to do this.

Dodd

[JWinter]

I put 4 1/4" rear warp 9 on my CRF 450 and I am using a 150 DOT rear and I had to shave off the edge of the tire for chain clearance. I have raced against Chuck for years and he had his bike set-up pretty well. Good luck with your project and I hope to see you on the grid for Colorado Class.

Jeff

[Dodd]

Sounds good. I spent 30 minutes on the phone with Woody today working out the wheel issues. Looks like at this point I'm going to have Woody's boys lace up a set of 17" hoops on the stock hubs. Its getting to difficult to source hubs for such an old bike.

Just got done with the paint on the frame, subframe and swing arm- its coming along!

[Bartman]

Go for a 5" rim if at all possible, it makes a huge difference. I had a 4.25 and a 5" on my CRF and would never go back to a 4.25.

[Dodd]

Got it- thanks Bart

[jgixxer1]

I also had to shave my 4.25" on my cr500 with a 150 DOT. Actually didn't shave it; the chain did all the work. I couldn't use that 1/4" of the tire any way; too pinched. That was when I read about offseting rim with spoke adjustments, but got rid of the bike before I did anything.

I talked to Chuck one time in the pits about his bike. He had a 5'' rear with a 165 slick and zero chain rub. He had rim offset and sprockets spaced with chain guide removed. He also had Madman engineering tranny gear which spaces out 3rd, 4th, and 5th. With 15/39 gearing I could only pull 105mph. He had the same 15/39 but could pull 120mph with the Madman kit. I looked it up and its $800 for the parts.

There's a guy named Rick Pearce who races a cr500 in AMA Supermoto Unlimited class. He runs a 5.5" rim with a 170 or 180 series slick. He had his swingarm notched and rewelded with aluminum plate. I seen a pic of it somewhere. If I can find the link I'll post it. That's going to great lengths and probably pretty pricey unless you know a competent welder that can weld aluminum, but well worth it.



p.s. just took delivery on that 650 berg mentioned earlier. It will walk my old 500 easy. Been wanting to do some mra stuff for the last 2 seasons. hopefully this will be the year. for cost reasons I'll probably have to get smoked by the 600's in superstreet first then get my license and meet you guys in colorado class.

[Dodd]

Nice!

Yea I was thinking about trying to find a way to space out the gearing, but in the interest of keeping it cheap, I'll prob. just stick to the stock stuff.

I'm sure I'll get my doors blown off in the CO class on the big straights but oh well. It will be nice to just get a race or two in this season. And if not, plenty of track days.

Woody from WWW told me that he sponsored Chuck for years, so I'm looking forward to what he has to tell me about building one of these.

Thanks for all the input, and if you find that swing arm post the pic. I do know some good aluminum welders-

Dodd

[jgixxer1]

Here's a link to notching the swingarm and there is another link within the link. I"m doing all this from my phone and the pics on the forum didn't show up. Maybe they will from a computer.

http://www.supermotojunkie.com/showt...h-5-quot-wheel

[Dodd]

Nice. I ordered a set of wheels from WWW today, went with the 5 inch rear. Once I get it back and can mock it up with the chain I'll see what I have to deal with.

Its coming along nicely!

[ducati7044]

I'm glad to see you still working on this project. I'm going to be racing my cr500 at the end of March with AHRMA in Texas. I hope to race with you in the MRA this year!

[Dodd]

Its coming along- Once I get the wheels put on, and the motor back in for a mock up I can see what I have to deal with for rear wheel clearance, and radiator room. I tossed the stockers, they were beat to death and was thinking about grafting in a smaller 500, 600 CC full radiator in front of the down tube. With the down sizing of the front wheel, I've got a good deal more room.

What are you running on your CR?

Dodd

[ducati7044]

I'm running stock radiators with the plastic rock guards removed for more cooling. I also am using a 4.25 inch rear wheel with 150 rubber. The chain cuts into it horribly. It looks worse than the actual damage done. I change rubber pretty often so it's not a big deal. Onlookers are shocked! I've run this bike from Daytona to Willow and have never overheated. Anymore I don't ride it enough to f#ck around with offsetting the rear wheel. Hell I'm lucky if I race it twice a year anymore. It does good at HPR. Before I cold seized it...(my fault) I was running 2.06's. And that was my first time there.

[Dodd]

Well if you never over heated a tuned motor, I'm sure I can get away with stockers for a stock motor. Thanks, that makes less stuff to do-

[AdamandNoahsdad]

Do you plan on doing any type of aerodynamic mods? Elimination of the front fender? clip ons? Cutting the radiator shrouds? Are you shortening the suspension?
Yes, I have a million questions. We are building a KX 125 to possibly run in the colorado class later this year. We can build it as a supermoto bike but we are curious as to any changes we would need to make for the higher speeds for tracks such as High Plains

[ducati7044]

On my bike Linderman redid my suspension. Lowered it. I also run a little bikini fairing off of an S1 Buell. I cut down the radiator shrouds and use renthal bars. I tried clip-ons once just for the hell of it!!! WHOAH! It was FUNKY! I had to go back to the renthals. I still have the front fender on it. The one big modification I did was have Jemco make me a down pipe for it. Really opened up the top end. At Portland last year I was radared at 131 mph. No lie! SV650's couldn't pull me on the 7/8 mile straight.

[Dodd]

Holycrap! 131 on a dirt bike? crazy! As for my build, I am trying to keep it under 3K- For plastics I'm running stock stuff (UFO) with what I believe is a kx 250 front sumo fender. I thought about lowering it, but in the interest of saving bucks I'm just revalving and respringing the front and a new valve in the rear. I'm hoping just to have it built and tuned in time for one race- even if its the last.

I didn't race last year, so I'm most likley going to have to take the class again, and then convince the rider director to let me go expert so I can run in the CO class. Lots to do!

Hopefully the wheels will be ready this thurs. when I'm down in town. Then if I can get some used rubber I can do a final suspension mock up and see what I can get away with.

[jgixxer1]

Colorado class requires expert status? If I can't run that class with a novice license, what class is a supermoto competitive in that a novice can run?

Not trying thread jack; seems like it pertains to this thread and don't want to start a new thread for a one post answer.