As I stated in my last post I just bought a 1982 RM250 to rebuild. It runs, It shifts, it doesn't make any abnormal noises. I have felt through the intake and at least so far the lower end bearings seem good. It does have low compression. If it passes a leak test and after I tear the top end down to rebuild it and if the lower end still feels good should I split the cases anyway or as my dad would say if ain't broke don't fix it.