While I was riding my 78 GS 750 it starting running very rough with symptoms of bogging, backfiring and very low top speed (40mph). I want to fix this myself but donĀ“t want to start trouble shooting to in the wrong place. I would be very appreciative if soemone with a good idea of how to fix this could share trouble-shooting/repair information with me. Here is what I know about the situation.