I would think you'd be safe to try the jets that are in there now, then check the plugs to see whether it's running rich or lean, and see how it runs. Jetting changes the air/fuel mixture. Unless your planning on gutting the airbox or something to get more air you probably won't need to add more fuel. And then theres the fact that sleds generally are already jetted rich from the factory. I bored out the cylinder on my quad .80 over and am running the standard jet size and it runs perfect.