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2003 YZ450f best hot cams?

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I have a question on hot cams. I am looking to rebuild my top end on my 03 YZ450 and I don't know what brand or stage of hot cams to get that would get me the maximum performance out of my bike.  I do a lot of dune riding. Some people are saying to mix stage 1 and stage 2 hot cams to get the best performance, but this is with a 250f, would it work with a 450 to mix them like that? and would boring out my piston to a 480 help? would I need to run race fuel with both hot cams and big bore? and what brand is the best on big bore kits?

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From what I have gathered cams for the most part on the 03-05 yz450's are like gaining 3 HP from some billet or chrome bling.  :devil:  That said I have a 470 bore and run pump gas no problem at all. If I wanted max HP I would go bigger bore higher compression and some sort of professional tuning on the jetting with race fuel. If it's sand drags you are doing a few hours on a dyno might help. To be honest a fresh 03 with attention to detail on a stock rebuild is one of the most brutal power deliveries that I have ever ridden. I have a buddy with a "factory" crf450x built by a well know race team here in CA with all the go fast parts on it and my somewhat wore out 03 is far more brutal on the bottom but his has more pull threw the top so it all kinda evens out. 


Good luck

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you dont need hotter cams. good air filter and carberated right and you ve got plenty of power on stock motor

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