Thanks Dave. Just a couple questions. I'm installing the hard parts 540 cyl. and 12.5 wiseco piston in my 04 450 exc. Got about 5000 miles on the bike now, and figure I should freshen up the cyl head at the same time. When you are installing the oversize valves, are you doing intake and exhaust? When you blend in the combustion chamber to the larger cyl. are you removeing the material by hand? How many CC's should I end up with in the combustion chamber to run on premium pump gas? Any info would be greatly appreciated. Thanks. Jingles.