hey, looking to up the jet size in my carbs on rptor 660r. got to rebuild the motor anyhow so i thought i'd make some small performance mods while i am in there, like raise the compression and add a hot cam. the jetting though sould be brought up but does anyone know an easy way to fique out what jet sizes to make it run at it's.... i don't wanna say best but more appropriatly with the mods, without too much trial and error? i'm sure the factory jetting is just gong to be too lean. thanks

 

The best you can hope for is finding someone who has similar modifications and rides in a similar climate/location/altitude. Even if you find someone running the same jetting it's still quite possible that you will still have to do some trial and error.

Figure out what components you're going to use as well as your intake setup and the many helpful atv riders on the inter net can help you get in the ballpark, then you can take it from there.