just a little info on my PRO-X's........
Pro-X piston kits are manufactured in Japan and are designed to be an O.E.M replacement (O.E.M stands for original equipment manufacturer ). This means they meet or exceed the manufacturers specifications. Most of the later models are actually genuine pistons in Pro-x boxes!!. Make no mistake these pistons are genuine racing parts.
The pistons are supplied in a kit form that includes Piston, piston rings, G-pin and circlips.
The aluminium alloy used in the manufacturing of Pro-X pistons maintain or exceeds the factory specification.
Pro-X pistons are precision ground on modern CNC machinery and maintain extremely close Tolerances. Nickasil cylinder pistons are available in standard sizes along with Fractional sizes e.g. (A,B, C,and D) which allow wear to be taken up in the bore e.g. size A is the smallest and D being the biggest please see tips on fitting.
Cast iron sleeved cylinders have additional Oversize of 0.25m/m increments up to 2.00m/m oversize, please see Reboring.
The fact that Pro-X pistons are made by the manufacturer that make pistons for Honda, Kawasaki, Yamaha, Suzuki, makes them the smart Solution for you to save money on engine parts.
Sux...they only go to a 2 over. glad IM only 1 over. lol