guys .....just wanna ask..especially to bro charge or alexei...
if a stock bike use a racing cam (high / low cam)...only racing cam..what will be the positive and negative effect to the stock engine?...tq

thanks man... I'm a two-stroker. Don't know much about cams. Take my words lightly.
Cam profile is a combination of 4 dimensions, and hi-cam is just one of it.
http://www.auto-ware.com/combust_bytes/camspecs.htmlMost likely, the hi cam that you get, will also have a more 'racy' cam profile.
In the end what you are MOST likely going to get, is same power at lower RPMs, higher max RPM, and more power around 6-9k RPM. See comparison of cam duration vs cam lift height in a car engine. Aftermarket racing cam is kinda like the BLUE line...
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Changing from normal cam to high lift cams, also means converting your engine to 'interference engine'. But, since LC uses timing chain instead of timing belt (like cars), there's no problem with that.
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For interference engines, when timing belt/chain breaks, the piston will kena the valve tapet that is 'open' at the time, and causing internal damages.
Another webpage about cam profiles, one page already, and I learnt a lot:
http://www.velocitimag.com/2010/03/cams-wh...g-duration.html