So I purchased this piston ring http://www.ebay.com/itm/171120907743?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2648 to replace the one on this 86 yz 125 im restoring (See the rollin turd comin through thread in the 2 stroke forum ). Its at standard bore which is 56 mm. I got the ring today and tested the end gap in the cylinder and its golden. Perfect out of the box. But, I go to install it to the piston and it doesnt seem to want to slip fully into the groove which makes it impossible to compress to fit the cylinder. It seems to be sitting on the outside of the groove, not the inside. Im installing it with a piston ring installer and not rolling it on with my fingers. There werent (arent) different thicknesses of these rings are there? If I match the new ring with the old ring, they look identical and I can put the old ring back on with no issue. It slides right in the groove. Im not sure whats up. Anyone run into this before?