Switching throttle bodies

1 reply to this topic
  • iceracer8

Posted March 18, 2011 - 06:59 AM


I posted this in the jetting section and didn't get much.

Looking into the idea of putting an 09 CRF 450 throttle body on a 10 YZ450. I know of the Simon Smart Body and have called on that. Looking for a bigger throttle body and want to go bigger than what the yz TB can be bored. Just from the stock number the CRF is 50 and the YZ is 44. Any info would be appreciated. From some of the numbers I have heard from the flow bench the YZ head is probably the best flowing stock head out there right now. Just trying to exploit this. I race flattrack so more power is always a good thing. Had the bike on the dyno last week and the numbers were good but as any racer knows they could be better.


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  • grayracer513

Posted March 18, 2011 - 07:02 AM


Contact Ron Hamp at RHC and ask him. If anyone knows, it would be him. He was the first guy I know of to get 60 honest HP out of a 5 valve head, and it took him years to get there. He's already built the 2010 to over 62 HP.

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