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Thread Like Summary
Total Likes: 2
Original Post (Thread Starter)
by DamienE
Hello all,

My 1970 Thunderbolt has been running good and I’ve been enjoying it. Tonight however I went for a ride and came to a stop at a light. Suddenly I see a cloud of acrid smoke rolling out from under the front of the gas tank! My first thought is fire!

I walk it to the side of the road. It’s still running so I shut it down and inspect the bike. No gas leaking anywhere, no oil (haha any more than usual) leaking onto anything hot. OK, no fire. I thought maybe the carb belched something up or something. Starts right back up and I’m on my way back home.

As I’m riding I notice that my headlight high beam indicator isnt illuminated on my headlight. My gauge lights aren’t on either. None of my lights are working.

I got it home with no issues and take the side covers off. Ugh, I see melted wire harness cover. The small red wire that goes into the wiring harness from the battery is fried and severed. All the insulation from the battery to where the cloth on the harness starts is melted and gone. I jumped the two parts of the melted wire with an alligator lead and the light works fine. My alligator jumper didn’t melt or anything.

I assume a short caused this but why didn’t the jumper melt like the original wire? Just an old wire that let go? Any common places to look? Doesn’t seem to be much accessible due to the cloth insulation.

I could run a companion wire from the battery to where the red wire terminates in the headlight housing But if this wire went could others be next? What would you do? Keep in mind this is no concourse bike. It’s a rider. I’m guessing a new wiring harness is in order. Any recommendations?

As always, thanks for reading and I appreciate your feedback!
Liked Replies
by gavin eisler
gavin eisler
Check the Zener mount and its connections , if it comes loose bad things happen.
1 member likes this
by triton thrasher
triton thrasher
The manual is misleading on fuse ratings if you’re not fluent in 1960s British automotive industry lingo.
1 member likes this
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