I have an austrian hirtenberger four bolts head , front induction. I bought the engine from ebay , my question is it has a single ring , but i feel it has not good compression . This ring is a little differente , it is not a dikes ring , it is a single ring with a groove around its surface . It looks like lubrification groove . I ckecked it , its is ok , but I feell it is has only a small spring action against cilinder walls . Is it normal ? Somehow when it will be running some adittional pressure will be formed , like a dykes rings?
Thanks for fellows help . Antonio