Road racing a 650R- Need more power!

I need advice from those who have been there and done that-

I am road racing with an '01 XR650R engine. I have the full HRC kit, custom airbox, Big Gun exhaust, open intake manifold, and the stock carb (with the HRC needle, 68 idle and 178 main).

I want more top end power, but I wasn't planning on getting into the inside of the engine again until it needed to be rebuilt. I also don't want to lose reliability.

Has anyone gone to one of the bigger flat slide carbs? I was thinking about a 41-43mm Mikuni or Keihin. Is head porting necessary to take full advantage of one of these?

Thanks,

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now