CR500- Road Race bike

Did you buy it? Where can I find the class rules?

 

I didn't buy it.... GP based bikes are not allowed in FS. I think stock frames only, so I'm sure this bike is not legal in that class.

Rules are kind of gray for this class....they don't say anything about 2 strokes but after asking, stock frame motards are legal.

Check AMA vintage days rulebook online for rules......or better yet call them.

 

I found the rule book. Formula Singles is 4 stroke only. If would be legal in 90's Superbike if it had a 1996 frame but was built on a 1997. The only class it looks legal for is Formula GP lightweight.

 

2 stroke are legal in Formula Single( I asked race officials last year).......dinosaur 2 strokes aren't listed because they don't stand a chance against modern 4 strokes singles!!! Lmao

 

Honestly, most of the time they would be correct. Most people only look at peak numbers however average power is what matters. A SV650 makes only a little more peak power over a CR500 however when you average the power over a 3000 rpm range the SV650 makes WAY more. This is why modern sportbikes are so fast and easy to ride. My R6 makes good power over a 6000rpm range (10k-16K). Although, I did say "most of the time" because I've been working on a big 2 stroke single for about 4 years now. It makes peak torque at 6,000 rpm, peak power at 9,200 rpm with good over rev to 9,700 rpm. It makes good power over about 3000 rpm. Which is about what my TZ250 had however this has 3 times the torque so the powerband is much flatter.

Dyno chart borrowed from some website:

 

I plead the fifth on peak numbers.....but the higher the peak, trickier to ride! There's a fine line between leaving black streaks and a ride in the ambulance....

I raced at Mid-Ohio VD and Wera Pitt National event and faired well against modern machines. I broke the muffler at MO and still managed to get 2nd against GP125 bikes(Gp Light) and at Pitt got beat by a cheater fzr400/600 bike(D superbike Ex) and a custom built Aprilia 550( Clubman Ex) Lmao
See if I can even the odds this coming year with some BIG motor changes!!

 

What chassis and engine are you running? I'm obviously using a TZ250 chassis. When I first built the bike I told people it was a cr500 engine but it's NOT. It has a 6 speed trans and a counter balancer.

 

Just an ole 91 cr500 dirt bike....lol

 

What part of the country are you from? Going to any vintage races this year?

 

You bet.....Mid Ohio maybe Grattan.....Ohio

 

I'm building my cr500 road racer I've race it in supermoto trim for a few years but the new big motor needs a better chassis wish you guys were in the southeast

 

Its hard to find complete rolling chassis so it easiest to buy a crf450 ($2k-2.5k) and sell the motor out of it ($1k-1.5k). I've used and would recommend: conversionparts500.com

Racers all like to keep their secrets but I'll let one out. For the best 2 stroke pipes:
Shearer custom pipes

 

I build an ex World Sports TZ roller with a nice CR500 engine once. Sold it before completion. Wish I
could of rode it though. Curious to know how you worked your 6 speed and also balanced the engine.
I was worried about vibration and heat at WOT for long periods of time.

 

I'm not using a CR500 motor.

 

Just saw this post. I built a road racer CR500. Its a 2001 aluminum cr250 frame with a cr500 engine. I put CBR929 forks on it and clipons. I shortened the rear shock. Using an RS250 tail and Ducati 916 upper, no lower. Had a custom aluminum tank but had a leak and not fixed it so just running the stock 250 tank. I fit cbr600 f3 wheels in it.

 

Would like to see your bike, throw up some pics if you got em

 

Sorry, I dont have an account that host pics. I will try and get a walk around video I did uploaded to youtube. The audio screwed up, but should give an idea of what I did. It will take me a bit.

 

you can attach them without a host...
When you reply to a post you will see three tabs at the lower left of screen, "Post Reply", "Upload a File", "More Options"

Just select "Upload a File" and you can attach them that way.

 

Here is my Cr500 AF I road raced a few times this year with WERA. Had to do the Beringer brakes because I couldn't ever get it slowed down...wasn't meant to brake from 118...

 

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