Backfiring

[slowride]

Here's another question. I forgot about this until something last night reminded me of it. On one of my last rides (October) the bike backfired a couple times. It didn't do it while I was riding, only when it had stalled and I was getting it going again. I want to so (so I will) it only did it twice. I had been playing with the throttle stop screw and it was a cold day. Later in the ride (when I'm sure the bike was warm) it didn't do it anymore. I have a 1981 GS850G and everything is stock on it. Anything I should be concerned about? I thought I better ask now while I'm still in the process of putting the last couple things back on the bike and I can still get at things if I need to.
Thanks.

Ed

[litshoot]

i'm by no means an expert, but if the bike stalled and upon restart backfired. it probably just had a little excess fuel that went to the exhaust and got lit up on startup. i've had friends do that on cars. they cut it off while driving down the street and when they let the clutch out it starts with a big bang and burst of flames from the tail pipe. i wouldn't worry too much about it unless you notice the bike acting different in any ways.

i've recently installed boyerbranson on my bike. you said you were messing with the idle. on my bike i have the timing a littl advanced but when the idle gets low it backfired a few times through the carb. just for the reason that the spark was early and the valve didn't close quick enough at too slow of a speed. make sure you idle is set right and your plugs read well.

[Dave8338]

Did it backfire through the intakes, or exhaust? It could be four things that I can think of or a combination of any or all.
1) Lean condition: carbs out of tune, o-rings in need of replacement.
2) Valves out of spec: reset the valves
3) Leaks in the exhaust gasket at the head, replace gaskets or tighten header bolts.
4) ingintion timing: adjust the points (if a points type ignition). Yours has electronic ignition-no adjustment.

[slowride]

It was too many months ago but I think it was through the exhaust.

Ed

[Dave8338]

Have you adjusted the valves? How many miles are on the bike?

[litshoot]

how much have you ridden the bike since you had the problem

[slowride]

About 15,000 miles on the bike. I have not ridden it since late October. I recently replaced the intake boot O-rings, spark plugs, cleaned up the airbox and fit it all back together. I was about to put the tank on and battery back in but figured I would wait to see if I need to do anything else.

Ed