Ok... My dad has an 86 cr250 in great need of a new piston and rings (the piston is missing a chunk...). It still ran great until recently when I think the rings finally died (there is like zero compression). I think the bottom end is still ok (it kicks fine and very smoothly). My dad has like no money to get the jug re-honed, etc., but he really wants to get it running. So...can we just pick up a new piston/rings/wristpin/etc and throw it in there and hope for the best? Assuming the bottem end isn't full of crap how risky is this? I know this is obviously not ideal, but it is either this or sell the bike broken... Thanks guys!