are the rings close enough for a drop in? or do most need to be ground?
depends on the age and condition of the cylinder. mine was an 03 purchased new, put in a 100mm wiseco piston in the winter of 04. ran that piston until 2007 when the cylinder started to oval, did a couple of re-rings to it in that lifespan (honed of course) but mostly to keep it reliable as we didn't see any compression issues.
measurement of the cylinder would be the place to start with that question, IMO it's worth taking the time to measure and order second, or make sure you can return it if you need a larger size.
