WIRING A GENERATOR BIKE WITH A MAGNETO

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tiparosa
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WIRING A GENERATOR BIKE WITH A MAGNETO

#1

Post by tiparosa » Mon Mar 07, 2011 4:08 pm

Sorry for the lack of knowledge but here ya go. Built a rigid with a 58 pan engine, but a baker 6 into 4 tranny in it. Need to wire a front light, back light, and brake light. I have the original generator in it, have a JP cycle regulator/rectifyer not installed, capaciter not installed, and fuze not installed. I need some help on the wiring for this to include which posts from the generator goes to what.

Thanks for the help. 1st time post for me but have been reading your forum throughout my build.
Tiparosa



RUBONE
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#2

Post by RUBONE » Mon Mar 07, 2011 5:06 pm

tiparosa,
Welcome to the forum.
You say you have the original generator. Is it indeed the original or is it 12V?
There is a ton of info on this in the knowledge base, did you do a search?
Robbie

kitabel
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#3

Post by kitabel » Mon Mar 07, 2011 6:25 pm

Shouldn't be a rectifier, it's already DC output.
Battery or not?

Bosheff
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#4

Post by Bosheff » Mon Mar 07, 2011 6:50 pm

The fact that yer runnin a mag vs. points and condensor doesn't mean squat to yer chargin system. They are independant systems and one doesn't care about the other....bosheff

RUBONE
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#5

Post by RUBONE » Mon Mar 07, 2011 7:49 pm

The fact that yer runnin a mag vs. points and condensor doesn't mean squat to yer chargin system. They are independant systems and one doesn't care about the other....bosheff
Sure the hell DOES matter if your running points, then you need a battery in the system! Mag can get by without one. And last time I looked, the battery was part of the charging system for points or electronic ignition!
Robbie

oldbob
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#6

Post by oldbob » Mon Mar 07, 2011 8:12 pm

I have been a fan of the mag fired no battery system for years. No need to be stranded along side the road because the generator quit working. I run a 65-A generator with a solid state regulator and have a battery eliminator in place of the battery.

Bob

indianut
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#7

Post by indianut » Mon Mar 07, 2011 10:40 pm

On my HD with mag, I run a 65A with a Bosch reg. Many years ago I was told by someone who knew more than me to TOSS the Battery Eliminator/Capacitor. I did and it has worked fine since. At least 20 years.

tiparosa
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#8

Post by tiparosa » Tue Mar 08, 2011 12:22 am

Not sure if it is a 6 or 12 volt generator. NO battery setup, just need the generator to run the light when the bike is lit. Regulator is from JP cycles, it has a cc rider box and says a voltage regulator 12 volt. Have a accell battery eliminator from JP cycle as well. I do not have them on the bike yet.
How to confirm a 12 or 6 volt generator?
How do I tell which post on the generator is the field and armature?

Looked in the tech area on the forum and could not find a diagram for a mag ran bike.

Thanks for the help,
Tiparosa

RUBONE
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#9

Post by RUBONE » Tue Mar 08, 2011 2:58 am

Look at your generator. It should have some numbers and letters next to the terminals. It could say model 58, model 61, model 65, model 65A etc. Those will tell what it is and if 6v or 12V. here is a wiring diagram I did for a friend a few years ago running a 12V gen with Bosch regulator. The only thing the capacitor does is allow the horn to blow if the bike isn't running and helps keep the lights from dimming at idle!
Robbie
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Bosheff
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#10

Post by Bosheff » Tue Mar 08, 2011 3:02 pm

Point I was tryin to make is ya run a different reg. for the mag vs one for a battery. No big deal. Mags are like any other part. They have their positive attributes and they have their negatives. It's all a matter of preference. Only major difference is ya got no electricity to power lights or accessories with a mag if the mill ain't runnin, and yer not dependant upon a battery to get it started....bosheff

Schwee
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#11

Post by Schwee » Tue Mar 08, 2011 4:00 pm

The genny model numbers that Rubone quotes are a good start, but not definitive.
I converted my 6V genny to 12V years ago by replacing the field coils and armature.

hogboy52
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Re: WIRING A GENERATOR BIKE WITH A MAGNETO

#12

Post by hogboy52 » Tue Mar 08, 2011 7:59 pm

If the generator is unmarked take the cover off and see which post has a wire going to a brush. That is the "A". The other is the "F".

Get a volt meter and with the engine running, check the voltage at the "A" terminal. A 6V. generator will run around 9V. unregulated.

I have a 62 Beemer that is 6V. magneto and will run fine with the battery removed, but when running through the gears, the headlight will go from dim to bright, and the regulator switch on/off. Each time this happens there is a very short over-voltage spike and the headlight could burn out in a few hours (a somewhat costly bulb in reflector unit).

The on/off-road BSA's had a Zener diode in a heat sink to smooth out the voltage spikes and a large condenser is used to serve the same purpose. A solid state regulator may act quickly enough to eliminate the spikes and and an ordinary 12V. sealed beam is probably sturdier.

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