Grizzly 800cc Big Bore Kit
Make your 660 into a 800cc Your cylinder, crank, and case are needed for modification. This kit punches your cylinder out to such a massive size that we have to resleeve your cylinder, stroke your crank and modify your case so it all fits. Also comes with a new hi-compression piston, hi-perf. camshaft, and all the nessecary gaskets.
I have a local shop runs this for over 3k installed