Hi,

i have a pro 2002, the mother all pro's, and the dealer is having a hard time to find me the original piston.

The original piston comes with a "dyke"-ring and normall ring.

I asked him to give me a normall piston but there seems a bit of a confusion abouth that the the cilinders differ from 2002 untill 2008, or so.

Is he correct? And also are there pistons nowadays who has intake windows in the skirt?

Thanks

Hi there,

I am not aware of any glaring differences between the 02 and later 250 cylinders. I am almost 100% sure that you can use the later style piston in your 02 cylinder without any problems, I don't think that you would find one of the older style pistons with a dykes style ring. From memory, the later model 250 just has transfer port skirt cutaways. I know what you mean by having the intake port cutaway in the back of the piston, it's not for timing of the inlet charge with a reed v/v motor, it may be to assist in scavenging after combustion. I have fitted later non intake skirt cutaway pistons to much older GG motors that previously had such an intake window in the piston, without any loss in performance. Give it a try.

Bye, PeterB.

Peter, a little late, but Thanks for the answers.

Rgds

George