[Kingragnar0313]

I just acquired a 2004 crf450r has a hot rod cam and crank t4 exhaust it needs a jug and piston was wondering what piston would be the best match for the bike any help is greatly appreciated

[JimDirt]

Welcome to the site !!

I guess it depends on what your plans are for the bike , is it going to be trail ridden ?? , track ridden ?? , just playing around occasionally ???

I have a 02 and I use the JE - 12.5:1 , I have over 400 hours on the track on that piston (stock for the 02 is 11.0:1) Stock for the 04 is 12.0:1 ......The more compression , the more bottom end punch and mid pull , the lower compression will give less of a hit , if you were trail riding and wanted a lot of low end grunt , then a 13.0:1 or even 13.5:1 , you can go up to 14:1 if you wanted , but the higher you go on compression , the more it likes better gas , anything above 13:1 I would say you need Race Gas , either mixed or straight , so take that into consideration when choosing , as the higher compression you go , the more finicy the bike will become ....power output depends on cam , gearing , type of riding , etc.

As far as piston brand , most all are good nowadays , even OEM , the top I would say are JE and Vertex and CP , but Wiseco and Pro-X all make good pistons , there are many options out there , there is not really a major brand that is bad .......the compression is up to what your needs are , and forged are better than cast ......... a JE is around $150-$180 , other brands go from $100-$180+

Hope that helps some

[Back2-2]

If I recall Vertex or Pro-X are the main supplier for OEM pistons for all the Japanese manufactures.