Ohm testing

NateDogg · Posted: May 2, 2009, 3:00 pm Post subject: Ohm testing

So I'm going through my charging system, My regulator is cranked all the way up and no increase in voltage at rev. I was testing resistance between slip rings and get 0. I zeroed the meter in first. Is this possible? from what I've read a bad rotor is usually low resistance (under 5ohms) not flat 0. Also, this may be a retarded question but here goes, does it matter where on the rotor you probe the slip rings? It doesn't have to be probed through where the brushes mount like they show in the manual?

jetmechmarty · Posted: May 2, 2009, 3:19 pm Post subject: Re: Ohm testing

It matters where you probe to the extent that you must probe each ring without contacting the other. In other words, you may remove the stator and probe anywhere on each ring. I'm not surprised you read zero. Original rotors are prone to fail.

ake sure the ohm meter you're using will read small resistance as in x1 scale. Reading K ohms will show a good rotor as shorted. If you read less than about 4 ohms between the rings, your rotor is toast. It will probably work if over three ohms, but you'll be walking soon.

If your rotor is original to the bike, it's only a matter of time before it fails. I good rewound unit should last indefinitely.

NateDogg · Posted: May 2, 2009, 6:59 pm Post subject: Re: Ohm testing

Thanks man, that's what I thought, Ill double check my meter but, the brushes are new, bikes not chargin at all and it's ability to charge seems to have declined over the past year and a half to nothing at this point.

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