I have a 2005 660 grizzly. It had a hotrods stroker crank, and a Yamaha .030" over sized piston installed. The engine displacement calculator tells me it now is a 702cc. Do I need to change any thing in the carb???? Bigger jet? Thanks.
You may or may not. Some have gotten away with the way it was. But this is not common. Most have to do a complete re-jet of the carburetor. Buying a jet "kit" usually makes this easier as it will come with multiple sizes of main and pilot jets so you can tune your carb properly.
Your best friend for carb tuning is patience.