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new rotor 5.5 ohms

beans86

New member
Hi all,

Any reason why a new rotor from Rick would come in at around 5.5 ohms? It's for a /6 so I was expecting closer to 3. Do the rings need to be lightly sanded and cleaned? There's definitely a film of oil covering everything
 
Rotor

Have you asked Rick? He will give you an honest answer. You trusted him enough to purchase the part from him. His reputation for customer is excellent. BTW, I am assuming you mean Rick Jones.

Friedle
 
5.5 ohms is no man's land...should be 3.4 or so. The earlier rotors were 6.9 and the later ones were 2.8. I would think that the meter probes should cut through the oil to make good contact.
 
When you measure such low Ohms test the tips by connecting the tips first. Some meters might already show some low resistance which you have to subtract from measuring the rotor.

For the measurement it might help to lightly rub the tips on the copper rings of the rotor.

My replacement rotor was cold 2.8 Ohms (3.3 according to specs) - yes, temperature also makes a difference when measuring a low resistance.

And Rick might tell you that what you measured is about the resistance for your model according to specs.

/Guenther
 
Not trying to disparage your meter, but are you sure it's accurate and zeroed?

At those small readings it doesn't take much to move an ohm or two.
 
When you measure such low Ohms test the tips by connecting the tips first. Some meters might already show some low resistance which you have to subtract from measuring the rotor.

For the measurement it might help to lightly rub the tips on the copper rings of the rotor.

My replacement rotor was cold 2.8 Ohms (3.3 according to specs) - yes, temperature also makes a difference when measuring a low resistance.

And Rick might tell you that what you measured is about the resistance for your model according to specs.

/Guenther

I'm dumb, meter measures about 3.0 on its own which would put me spot on. Bike is charging at a healthy 14.2 volts at barely 3k rpm! Thanks all for your help!
 
I'm dumb, meter measures about 3.0 on its own which would put me spot on. Bike is charging at a healthy 14.2 volts at barely 3k rpm! Thanks all for your help!

Sign up for harbour freight coupons and get their cheap digital meter for 10 bucks or less. Some sales lately they give you one for free if you buy anything else! :dance

They will measure better than the one you are using now. I've checked one against my Fluke which is a decent unit and they are bang on.
 
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