I own an 05 YFZ450. It has some mods done to it. But i read that you could buy the crank that goes on the YZ 450F dirtbike and you could put it on the YFZ450 and it would bump your cc's up too 449 or 450. I was wondering if it was worth the money to do it..

THNKS Jamie

 

Until you spend the cash for porting, aftermarket cams, etc don't waste your money.

 

Isnt it all ready a 450cc Engine?

 

It's 439cc.

 

Yeah its a 439CC. I got a questions you said i am waisting my money unless i get it poted and some new cams.. Since i have to cam mod done too mine wouldn't that be kinda close to buying new cams?

 

Advancing the cam a couple degrees is nothing like new cams.

Yeah its 439. Yamaha built it that way so that they could meet the 440cc class rule for the AMA. Well, as soon as Honda released their 450 which is bigger than 440, the AMA changed their rules so honda could run the bikes. Honda owns the AMA and Chevrolet owns NASCAR. Its the way of life.