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'73 Harley- Electrical Emergency!

Ok, biker boys (and girls), I need help. After sitting all winter, I fired up my '73 Shovelhead. I had a battery charger attached (charging 12v @ 6 amps). The bike fired up on the fourth or fifth kick (YAY!!!), but then promptly fried the headlight, the taillight, and caught the charger on fire (in the carport). What do you think is wrong? Defective regulator? Poor regulator ground? I want to ride this weekend, so help me ASAP!!!!?

15 answers
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Apr 13, 2009. 12:30 PMlemonie says:
Ooer! The charger was connected when you kicked-it over? Does your bike run or are the electrics 'toasted'? (don't know) L
Apr 14, 2009. 10:22 AMlemonie says:
Without the charger, I wouldn't imagine you could cook the bike anymore. I'd be inclined to try it - what's "going on" already has and it was probably related to the charger? L
Apr 14, 2009. 11:40 PMlemonie says:
I've blown 12V halogen spots with an unregulated 50cc scooter, but only at full revs (~20V). I guess you'll be able to see whether the regulator appears to be defective by slowly increasing the throttle?

L
Apr 17, 2009. 10:58 PMRishnai says:
Wow. Sorry to hear all isn't well in the land of the bikes. I'd be inclined to blame it on the charger unless you've done the same exact procedure before without causing damage. Otherwise, I'd look at the regulator a little funny until I put in a known-good unit...even if it didn't blow the lights when you tested it without the charger.
Plus I'm a little jealous that you're not snowed in like this snow-country chump.
Apr 14, 2009. 5:37 AMNachoMahma says:
> I had a battery charger attached (charging 12v @ 6 amps). . That sounds a lot like a bad battery. . > fried the headlight, the taillight ... Defective regulator? . If you fried two incandescent lamps, I suspect high voltage (bad regulator). Could have just been coincidence - I've seen weirder things happen. . > Poor regulator ground? . Cleaning all the connections (including grounds) would probably be a good idea. I use a little bit of bulb or silicone grease when I put stuff back together to hold corrosion at bay. . > I want to ride this weekend ... . If you plan on riding south, stop by and say hi. PM me for address/telephone.
Apr 13, 2009. 2:54 PMfrollard says:
its possible the way the charger was attached boosted your battery voltage (if it was in series) from 12 volts to 24 volts...if that happened, by a stretch of the imagination, your lights would blow pretty quick...
Apr 14, 2009. 2:34 PMfrollard says:
yeah, + to +, - to -...couldn't yield that result...its...weird.
Apr 13, 2009. 2:31 PMroboteen says:
get it to a repair shop it might be you left the charger on to long was it on all winter

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