Anyone know what would cause my 85 flhtc to miss when I turn on the head lamp? The bike runs great with no lights turned on and up until yesterday if the head lamp was on. As soon as I added any other lights, it would start back firing and missing. Yesterday it started doing this when I turned any lights on. I have checked the charging system per the manual and it looks like there are no issues there. I put in a coil pack, wires and plugs. I had the same issue last year but it was intermittent. Seems to be getting worse. I don't want to just throw parts at it and hope I get it right. Any suggestions? Thought it might be the ignition module, but don't know how to check that without replacing it.

 

Hi from the UK and welcome to HDF. I suspect you have a charging problem, possibly poor battery. What is probably happening is that the extra draw when the lights are on is stealing voltage from the ignition system. Call into the Evo section, where you will find experts and plenty of helpful advice. There is a Sticky over there by Dr Hess that is a good place to start.

There are also two Stickies at the top of this section on checking your charging system.

 

Looks like I have a bad ignition light switch. Of course the switch is now obsolete and there are no after market replacements for it. Does anyone have experience with a work around replacement? I am ok with relocating or remounting a new switch. Would like to keep the ignition and ignition with lights positions if possible. Thanks

 

As I suggested above, call in the Evo section. I can't answer your question, but there are owners there who most probably can. If you look at the count of posts read in here, compared with the model-specific sections, you will see that far more members use them than this one!