Hey everyone, I just went on my first somewhat long ride on my 81 and it did great shifted perfectly, brakes were great. When i got back to my crib i left the bike running for a few mins and noticed that it was doing a kind of back fire/spuddering thing. I took it for another ride and all good, had plenty of power with no struggle. So i pulled the plugs after the second ride and they looked good, no blackness or anything. Not sure if this is due to needing a valve adjustment or maybe bad fuel??? Any input on this would be great.