Stator Q's

[jeffroot]

I have some basic questions about a stator. Specifically this one is in a motorcycle.

The stator in question is static, has 8 posts, and 2 of them are wound for an ignition circuit. The remaining 6 posts are empty. I am planning to use them for a lighting circuit. Lets assume the lighting circuit comes from the stator as ?V AC, goes to a switch, then a 12v shunt-type regulator/rectifier, then to a 55W headlight.

Q1: If I wind the extra posts to make the lighting circuit, close the switch and run the lights, does this increase the load on the engine? I know its seems like a stupid question, it does right?

Q2: If I wind the extra posts to make the lighting circuit, but leave the switch open and do not run lights, is the engine still feeling the extra load from the stator?

 

[TurbineGen]

Is this really an 8 pole stator? They're usually 9 or 12 for an inrunner, and 12, 15, or 18 for an outrunner.

Q1: Yes.

Q2: It will feel some from the drag of the stator, but not as much as if the switch is closed.

Out of sheer curiosity, what bike did this come from? It sounds like it's an old Vespa. I think they had a goofy 8 pole stator on their older 150 model.

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If it is broken, fix it. If it isn't broken, I'll soon fix that.

 

[jeffroot]

It is a 150, Honda CRF150F to be exact. Basically a kids trail bike.
Here is a picture of the stator that shows the 8 posts and the 2 that were wound for the ignition. -

http://photos-a.ak.fbcdn.net/photos-ak-snc1/v1977/138/112/579926962/n579926962_2150864_6376205.jpg

Thanks for the answers!
About Q2, you say it will feel some drag when the circuit is open, why is that?

 

[TurbineGen]

The magnetization/demagnetization of the iron takes energy. This will also generate eddy currents in the iron as well which cause further drag. Spin an electric motor sometime. The same forces act on it to slow it down.

------------------------------------------------------------------------
If it is broken, fix it. If it isn't broken, I'll soon fix that.

 

[waross]

I think that the stator is already in place so the magnetic drag will already be there.

Bill
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"Why not the best?"
Jimmy Carter

 

[jeffroot]

Bill,
This was what I was wondering about, whether the drag was already there before the extra windings were added (assuming the lighting system is turned off).

 

[majesus]

SWEET a CRF150F!

Without any load what-so-ever the drag will be very minor.

Go to some motorcycle dump and get a voltage regulator, most of them these days have the rectifier and DC reg all in one unit, flush mounted to a heat sink which can be bolted to the bike's side frame.

I've done that with my RV-90 when I installed a head light on it.

Also once my DR-400Z rectifier/regulator blew. Dealer's price was $250, the guy at the motorcycle dump wanted $15 for one I grabed off a Shadow. Rewired the pin connectors and it still works.

Maj

 

[jeffroot]

I've got some new questions now....
I wound the stator, did as Maj suggested and found a one piece regulator rectifier unit (12V DC output, rated to 160W). I installed the new stator in the bike, wired the rec/reg unit and then I just plugged the leads into a 20W bulb that I had lying around.

This is a kickstart bike with no battery and I dont have a battery in my new circuit...

The bike fired up and the bulb was lit at idle. As the rpm increased the bulb grew dimmer, at ~1/4 throttle the bulb was dark. I put the voltmeter to the leads and watched the voltage drop to zero as the rpm increased.

What wound cause the voltage to drop away as the generator speed increased? I talked with a few people and someone said that I need a battery in the circuit to act as a capacitor. I'd think the reg/rec unit would be able to supply 12V w/o needing a capacitor....

Any ideas??? I wound this stator myself and this is my first time doing it, so dont assume that I didnt make some kind of stupid mistake there....