Right Handle Switch Burnout a symptom of anything?

Howdy all - long time since I've posted anything. Well, it was bound to happen, after 2+ years without leaving me on the side of the road, my old girl got cranky and did just that.

Was cruising along and felt the engine cut out once or twice within a mile. I assumed it was a carb gas issue and so i sort of worked a clutch/drop start thing and the engine seemed to pop back on. Then it cut out for good and as I coasted to full stop the right handle switch was pouring magic smoke and smelled like death. repeated attempts to kick 'er over yielded no sign of life. My assumption is that the kill switch gave up the ghost and a replacement of said right handle switch cluster will remedy. That switch assemble was definitely old and tired, but I'm also wondering if it burning up might be an indication of some sort of other power/charging issue, rather than just being long in the tooth.

For what it's worth, the engine was running very well just prior and I was out testing/enjoying the benefits of a carb bench synch I'd just done. other potentially relevants:
-78 1075 A2
-new combo reg/rect
-dyna s + dyna coils
-agm battery
-haven't been using starter as there's been a short somewhere in my electrics, i think due to wear/bare wires uin my tail section?, and it hasn't worked. but this has been the case for a while and I've been kicking/riding it without any issue at all.

any insight or recommendation on where to find a good replacement right bar switch much appreciated. thanks all - and good riding!

Is wiring inside the handlebar?

nope - external to handlebars. has superbike bars and my guess is that, while old, the switches aren't original either.

just spoke to Rob @ Z1...looks like they do have a switchblock that should swap well. however, any thoughts on whether this is likely symptomatic of any specific electrics voodoo, vs plain old age, would be much appreciated.

thanks!

Would guess corrosion inside the switch.

Here's a suggestion, compliments of wiredgeorge:

You can probably jerry-rig one of these switches but the older ones will have some functions not found on your bike... for instance, the headlight switch on my 76 KZ900 has an OFF/PO/ON setting and the kill switch has two OFF positions... the problem with any old switch is that the contacts oxidize and all these old switches can be disassembled and the contacts cleaned. Your switch likely has a button contact with a plastic button holding a piece of brass metal on the back which contacts a thin metal plate. This stuff WILL oxidize and not work and most of the old switches have this problem. Carefully disassemble this stuff and clean it with some very fine grit sandpaper and then coat it very lightly with dielectic grease and it will likely be fine and work just as well as the old switches you are contemplating buying... recently, two right hand switches came up for sale which fit my bike and these switches were NOS (new). Both went for almost $150 (ouch)... If you do decide to get a used switch, get one from any bike with 7/8 bars and a compatible throttle housing (one integrated into the switch) but get one from a newer bike and figure the wiring out... the older ones will share the problems you are trying to fix. Try to fix yours first then get a newer used one if that doesn't work...


Good Fortune!

sweet; thanks Patton, and to WiredGeorge. Both you dudes have guided me through many a snaffu & i much appreciate the advice.

i'll yank it apart this evening to see if I can identify causal corrosion, but I think I'm going to try to replace the whole damn block with a new one from Z1. they're unit seems reasonably priced. I assume there will some wiring hoops to figure out w/ the swap....i'll report back.

Allright - so swapped in a new right handle switchblock from Z1 and she came back to life. The new block is not a clean/direct replacement; seems to be made for a slightly smaller diameter bar/throttle. It cinches up ok, but there's definitely a gap and if I torque it down hard enough to get the two halves to seat, significantly impedes the throttle snap. But it'll do for the moment I reckon as I see about rebuilding the corroded/burnt one.

Wiring hookup was also, ahem, 'a little' wonky. Though frankly it's more a reflection of the state of my overall harness than the new part. The two hots coming out of the kill and starter switch splice into on hot harness lead. And there's no hookup for the right hand light switch. But, like, I said.....it runs. Remains to be seen if this fryout was the causal factor or a symptom of something hairier.

One thing is for shite sure.....I'll be replacing my entire main harness this coming off season. If I make it that long. It's horrible in there...a rat's nest of old wiring splices and part-melted casingings. I reckon the iron butt run a year or two back is partially at fault for the meltage.

thanks again for the help and will report back as /if I learn more. And when I manage to coax my electric start back to life.

onward!