Hey guys.

I have recently purcased a 2004 YFZ 450. I was happy with the performance for a while and then i started wanting more. I have replaced the exhaust and put a bigger axle in it.
I was hoping that someone may be able to tell me what i can do to make maximum hp. I am also not happy with the top end speed so i am hoping someone can tell me what to do.

Thanks... Paul.

 

The YFZ comes from the factory highly tuned. You can put in some wilder cams and a piston with more compression. But the gains will be minimal. Try going one tooth up on the countershaft sprocket for more top speed.