just checking that they all do that............(1982 FLH completely stock, bar the new mustang seat)....motoring along and i turn the switch to "lights" and she lets out an almighty backfire...iam thinking the gap between the two positions on the switch is big, so the twin fire coils light up any unspent fuel? Also if iam stopped at a set of traffic lights and turn on the lights, she cuts out........am i right? they all do that?

 

Sounds like you need a new battery. My Vulcan 750 did that.

 

If you're using the switch on the tank , it's cactus !
They go there all the time on older bikes.

 

I think the newer switches don’t do that, like when HDstarted electronic ignition.
I’d suggest using a helmet and headlight every time you ride, but that’s just my opinion.

 

Ha ha you funny.
My old tank switch would spark sometimes when I was gassing it or if I hit spine jarring bumps.

 

Mine cuts out when I turn on the lights too. And I completely cleaned and greased the ignition switch. Didn't help. Not a big deal since the motor comes back to life when the switch is in the lights position.


carl

 

sounds like there is a jumper wire missing between a set of contacts .

 

I agree to always using your headlights. Recently replaced the tank switch and yes there is a gap between no lights and lights on. A backfire would be normal and not a real issue when switching between no lights and lights. As a kid we used to pull up on a friend and switch their bike off at the handle bar. When they reengaged, wow what a backfire!!


What made me look into this is my bike was having trouble engaging the starter with the lights on.

 

update...i went on a 800 mile ride on the weekend and 500 miles into it,the bike started to pop and bang, so i jiggled the switch a bit with some luck, only to have it do the same a few miles down the track... so the switch is cactus ..i'll buy a new one and take it from there.

 

I upgraded my old-style flat key stock switch with a barrel-style from JP Cycles. I know, I know there are folks that swear they are junk, but it was fine on mine for a long time at least until it went down the road with a new owner. It was a helluva lot cheaper than factory too. https://www.jpcycles.com/product/3800420