Author Topic: burnt wiring  (Read 1165 times)

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Offline aaron h

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burnt wiring
« on: May 21, 2015, 12:17:29 PM »
Hello all, recently purchased a running 72 cb750 and the guy told me it only runs in ACC position, does nothing with key turned to RUN. I said ok and rode it for about a week till it died with no start back.

Pulled off tank snooping around and found this burnt plug and where some one spliced some wires together. My question is what goes where that blie butt connector is? A fuse?

Offline madmtnmotors

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Re: burnt wiring
« Reply #1 on: May 21, 2015, 01:09:28 PM »
The blue (blie?) butt connector is a crimp connector with a heat shrink casing. Definitely not stock. Looks like you have your work cut out for you.
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Wilbur



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Offline aaron h

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Re: burnt wiring
« Reply #2 on: May 21, 2015, 01:13:14 PM »
Right, I agree, not stock. I can't find a wiring diagram to show what those wires were sopposed to do. Ordered a new ignition switch. Still trouble shooting, why  I lost fire.

Offline flybox1

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'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Offline aaron h

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Re: burnt wiring
« Reply #4 on: May 21, 2015, 01:38:17 PM »
Ha! Thanks flybox, I'm on that site now and my carts pretty full as is.  Would definitely remedy the problem tho wouldn't it

Offline mrfish2

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Re: burnt wiring
« Reply #5 on: May 21, 2015, 01:41:54 PM »
A new harness is really your best/easiest option. There's no telling what kind of other wiring monstrosities there are hidden inside the bike haha
1976 CB550K            1979 XS1100
1980 CB650C - Sold

It's a little motor and likes having the tits revved off it.

Offline aaron h

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Re: burnt wiring
« Reply #6 on: May 21, 2015, 01:48:21 PM »
Well case closed, new harness for me.

Offline ekpent

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Re: burnt wiring
« Reply #7 on: May 21, 2015, 04:03:52 PM »
 I noticed your bike has aftermarket coils so probably other mods also, some maybe not so good. Good luck, new harness is a pretty big job. Make notes or pictures how the old one was routed.

Offline aaron h

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Re: burnt wiring
« Reply #8 on: May 21, 2015, 06:32:38 PM »
Thanks for tip, that's a good idea. This bike is someone else's project so I have some work ahead of me.