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boring yz450f carb?

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So I was wondering and also have read that boring the yz450f carb makes a big difference. I have right now a 2006 yz450f that I drag race ( dirt drags 500ft) I had the head bench flowed and ported I put stage 2 hot cams in it which I am not very impressed with it did not pick up much at all really stayed the same. I also put a je 12:8 piston in.. It should have made a big difference then it has. I think it is there just something is holding it back.. So my question is how knows these 450s like who should I talk to that can or knows theres stuff and what about this boring the carb will that help and what kind of difference will that make?

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The Yamaha heads, with the 3 intake valves don't flow very well at all.

The valves open 50% as high and as long as say the CRF450r head

You could swap carbs between a YZ450 and a CRF450, both with ported heads, and the CRF will always flow better. 

Both bikes use the same carb.

I don't think it has anything to do with the carb.

My WR head was ported stage 3 ( wide open flow)  with the HC stage 2 cams, and it's still pretty peaky, and not that fast.

 

Unless you get the cam to open higher and farther, it will never flow much better.

The valve system and the HotCam profile are the choke points in my opinion.

 

IMHO, Hot Cams products are very poor designs. Never experienced good results with any of them on several bikes.

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I feel the same way now about the hot cams not happy with them.. I think the stock 06 cams worked better to tell you the truth.  I have been reading up on the web cams and they are much bigger and would do what you where saying  keep the valves open more and longer. 

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Yeah, I am going back to stock WR intake and YZ exahust (WR and yz intake are identical) as the power delivery, though not as aggressive, was much wider and more linear.

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