Hi everyone...Just like to say what a great site this is with lots of great reads and helpfull tips.
Ive got a Yamaha gp1200 1998 that is in need of an engine overhaul. While i had the engine apart i was going to port the cases and polish ports(not change just clean).

The only other mod i run is aftermarket filters and was woundering with the cases being ported will i need to change the jetting?...If so what do you recomend?