15 amp breaker

Electrical issues
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geareater
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15 amp breaker

#1

Post by geareater »

Why in the world would someone have a 15 amp breaker between the neg terminal of the battery and the frame ground point ? This is on a 58 flh, have checked several of the wiring schematics on the site and no find anything like this. Thanks
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Cotten
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Re: 15 amp breaker

#2

Post by Cotten »

Geareater!

It was either most convenient, or they just didn't know a fuse or breaker should be on the positive lead.

The MoCo wasn't advanced enough to have any at all!

....Cotten
1950Panhead
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Re: 15 amp breaker

#3

Post by 1950Panhead »

Why in the world would someone have a 15 amp breaker between the neg terminal of the battery and the frame ground point
Why in the world you ask? Cause if there is a dead short the wires can get red hot setting your pan on fire resulting in a big lump of charcoal.
A fuse or breaker will work on either side of the battery since the elecrons go round and round.
Jerry
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Re: 15 amp breaker

#4

Post by FlatHeadSix »

Harley-Davidson put the fuse and/or the ammeter on the negative side of the battery on all the Harley lightweight bikes that came equipped with one. A fuse or circuit breaker is just as effective on the negative side as it would be on the positive, works the same either way. And, as Jerry just said, its a good idea.
mike
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Re: 15 amp breaker

#5

Post by Cotten »

Folks,

When the MoCo finally did introduce a breaker on Big Twins,
(late '65 or '66?),
it was connected to the positive.

The reason is beyond my electrical understanding,
but I bet I can dig it up without google.

....Cotten
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Re: 15 amp breaker

#6

Post by Larry »

The breaker is on the feed side of electric start motorcycles because the starter motor grounds through the chassis and draws more than 15 amps.
58flh
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Re: 15 amp breaker

#7

Post by 58flh »

Hey GUYS!---I have always run an inline breaker or fuse off the positive cable!,& I also run 3 grounds in various places on the bike. Never Had A PROBLEM running this way!---The x-tra GROUNDS ARE a GREAT HELP!/Best on rigid-framed machines. Once I stalled out many moons ago,& it was a ground at the Frame from Batt.!--That was the last!--I added 2-more for a total of 3 & never had an issue AGAIN!
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Re: 15 amp breaker

#8

Post by Hog54 »

I was told 30 years ago to always run the breaker on the negative side incase of a short in the wiring.
PanJud
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Re: 15 amp breaker

#9

Post by PanJud »

FlatHeadSix wrote:Harley-Davidson put the fuse and/or the ammeter on the negative side of the battery on all the Harley lightweight bikes that came equipped with one. A fuse or circuit breaker is just as effective on the negative side as it would be on the positive, works the same either way. And, as Jerry just said, its a good idea.
mike
That's how I do mine--there's a very convenient tab right by the negative battery pole where one side of the breaker mounts.... if that's the ONLY place where one side of the battery gets into the ckt, I fail to see the difference (unless you're wanting to get into that 'conventional' vs 'hole' theory thing)
Cotten
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Re: 15 amp breaker

#10

Post by Cotten »

PanJud wrote:... I fail to see the difference (unless you're wanting to get into that 'conventional' vs 'hole' theory thing....
PanJud!

Is that where electrons are negatively charged, and attracted to the positive?

It was a half-century ago when I was taught that, so it is surely wrong.

....Cotten
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Re: 15 amp breaker

#11

Post by Pomike »

I am looking at the Jan. 17, 1966 HD service bulletin, # 532.It shows the breaker between the + post on the battery, to the B post on the regulator. Do it any way you want, but that is how HD did it. Mike
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Re: 15 amp breaker

#12

Post by PanJud »

Cotten wrote:
PanJud wrote:... I fail to see the difference (unless you're wanting to get into that 'conventional' vs 'hole' theory thing....
PanJud!

Is that where electrons are negatively charged, and attracted to the positive?

It was a half-century ago when I was taught that, so it is surely wrong.

....Cotten
Yah...that's 'conventional'.(actually, I think I ought have called it 'electron' theory...been many years)....'hole' theory suggests the LACK of an electron flows the OPPOsite way.(Prolly does it the other way in Australia :lol: ) ( Strikes me as philosophical-type discussions....the answer, either way, doesn't really amount to anything that helps you through your day). I went for a decade or so without ANY fuses or breakers....had more than a couple wires turn into blackened pieces of copper. When I rewired it a few winters ago, finally broke down and put a breaker in (Owing to the price of an after-market harness, I fond a place in Maine that sold cloth-wrap wire. Colors aren't right, but it's better than car wire)
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Re: 15 amp breaker

#13

Post by KELD »

nup, never heard of a breaker or fuse on the negative, but willing to be convinced.
flatland
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Re: 15 amp breaker

#14

Post by flatland »

Been chasing those pesky electrons around for 30 years, that’s a Bi metallic breaker in the picture, heats up and opens the circuit. Problem is, most of the time you can figure + - 5amps from what they are marked and they may or may not work anyway. They belong on the load side or positive side, not the ground or neg side. Unless ur riding an old positive grounded something or other.
awander
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Re: 15 amp breaker

#15

Post by awander »

Larry wrote:The breaker is on the feed side of electric start motorcycles because the starter motor grounds through the chassis and draws more than 15 amps.
But the starter motor also gets a positive feed that draws more than 15 amps.
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