Jumby
Registered User

Hi Jumby
I'm interested in your posts about CR500 porting and mods. I have a street legal 500 that I offroad as well.
I'm purpose building a snowbike ,google timbersled mountain horse kit if you haven't seen them, and will power it with my CR500 motor. I'm looking for a as much torque over a wide powerband as I can get.
I suppose some case porting would be involved to really make the motor reach its potential.
Any information you can throw my way would be appreciated.
I live in Squamish, ph# 604 834 4659 or email farnhamscott@hotmail.com

Got your message thanks very much. I'll study this for a while and will probably have to ask you some questions later. Thanks heaps I appreciate it a lot!

did you not get my last message? It said what you needed to do. I will resend it if you need. Dont worry about a pipe right now, the exhaust ports and the head is all you need to do.

I have two cylinders - one was supposed to be ported one is stock. I put ported one on yesterday and it didn’t really make a difference. I had a quick look at the 2 barrels side by side and the ports looked the same just rounded and smoother on the one they said was ported. I measured the height from the top where the head cap sits to the top of where the exhorts meets the piston and there was only half to 1mm difference in height between the stock and ported one. The ported one was closer to the top so does this mean it was lifted 1mm?

How to stop my bike feeling like a tractor lol

The engine is pretty stock atm has a pro circut pipe and rad valve. I find that the bike has little top end, and to be honest, I really expected a lot more out of the motor. What would you recommend to get more power out of the bike? I will do whatever it takes! Have you used a dep pipe? Are they definitely a top end pipe? None of the suppliers will say too much about them and I have found one with no silencer at this stage.

What do I have to do to the head and barrel? I am really not that smart with engines (I can do a top end rebuild and have had the top end apart on this motor but that is about all I have done).

Hi Jumby,
My name is miller I was just searching on Google for some information on performance mods for a cr500. You are the only bloke I can find that seems to know what he is talking about when it comes to cr500. Would you be able to help me out with my bike? I am really having trouble finding someone that knows there shit. Thanks

Hey John. I may be interested in coming down on Friday for practice. Can you give me a call. 604 307 1065. Thanks Ross

hey daddy got any sleep lately...lol