ur gonna need another one or atleast new springs to make it run good wit porting. porting will give u about anohter 5-7hp

 

how can i shave of 0ver 40 pounds

 

how fast are yfzs

 

floorboards, oil injector, lights, starter, battery battery box, different handlebars

 

Yeah, can tell ya what to do. You can Recultch it, put a Wiseco Pro-Lite Piston in, Bore it out. It's almost like a snowmobile. Heck, we worked on a 1999 Scrambler 400, all we did was put a Wiseco Pro-Lite Piston in and new seals and the kid said flys after we touched it. Also we plane the head .020

 

mine does 75 with the parts i have when i get my clutch kit will get to speed quicker i can't wait, they do 64 or 66 stock most people underestimated the polaris 400s geta pipe and clutch kit first then tear down that engine port it get it milled then get a wiseco prolight piston and v force reeds mabey get a bigger carb or bore your stock one it will be a very scarry fats motor and to help it out loose some weight

 

You dont need top speed to race in the utility class. Well, I doubt it anyway considering I dont think the race would be all top speed, unless you are dragging or something.