I have a 2000 Yamaha Warrior. I have been looking into installing a big bore kit. Although I'm lost when it comes to this kind of stuff. What all is need to be done with a big bore kit? I mean does any head work need to be done? What about cams, cranks, carb work, etc.? Also, what kind of compression should I be looking for to be able to run 91 octane?

 

Let me know when you figure it out. Might do that to my 96 warrior

 

These guys sell a 370 big bore kit. An other rout is porting,High compression pistons,racing cam and valve work. Yamaha Warrior performance kit.

Should work on the 350 Big bear,wolverine,Raptor and Grizzly/Briun they all use the same DISPLACEMENT 348 cc
BORE X STROKE 83 x 64.5 mm
Motor.