backfiring issue

69 Commando 750 was running fantastic than after sitting for 2 weeks I rode approx 50 km than noticed that it would backfire at times. Slowed to make a turn off and than started backfiring frequently at lower speeds. Checked it over with the limited tools I had on the side of the road but did not find a cause. Limped home and tore off and cleaned the carb (Mik) figuring that should do it. Nope. Cleaned than changed plugs, nope. checked over exhaust system and tightened just in case, nope. Would start on first kick and idle beautiful so didnt think it would be the timing so checked fuel cocks and reinspected the carb, still not the issue. Finally looked at electrical and turns out the Boyer connections were loose. Back up and riding! Funny thing is I was later reading this forum and which noted the stuff I checked than came across a post that said that usually an issue you think is fuel related turns out to be electrical and I had to laugh. Should have thought to check.
Cheers!
Ekvin

Good work Ekvin, even if it was in the reverse order.

It aways happens when somethink plays up and usualy its always you go through everything you think could be wrong and find its in the last thing you didn't expect.
Boyers have had problems with lose or broken wires in the pick up but they are a reliable ignition, I ran my Boyer for over 30 years without any problems at all, never had a issue with lose or broken wires as other have had, maybe I am just lucky or I install things with that little bit more care.
Good that you sorted it out and you will know where to look next time it happens, but then it might be something else.

Ashley

When you start tuning for max performance, you often find that problems with the ignition system can give the same symptoms as carburation problems. There is always a balance to be maintained between ignition advance and mixture leaness. It is about combustion temperatures and detonation.

Be aware. Lazy spark plugs can give similar symptoms as well. I always carry a pair of new plugs because I have been caught out.

Dereck

I use a double-ended coil off a Honda with my Boyer. A while ago for the first time ever, the bike refused to start at our local circuit. A local 'expert' tried to help by adjusting the idle screws. I just watched him and said nothing. Then I borrowed a couple of plugs and a spanner and started the bike and re-adjusted the idle screws. The bike had been standing for a long time and I think the carbon or condensation on the plug had started conducting.