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Discussion Starter #1
Hi everyone,

My bike has been having problems with the charging system. Recently, I noticed the battery was losing its cranking power, every day in the morning the cranking would get slightly slower than the day before. Initially I thought it was just the old original battery going bad, specially since the bike had very little usage during December and January. Anyway, a couple weeks ago I bought a new battery and everything seemed ok. Then last week the same problem started appearing, the battery was getting weaker by the day. Last Friday when I got home from work, the battery barely had power to start the bike, and the next morning it just wouldn't start or crank at all, just a clicking sound from the starter. So I followed some youtube videos on how to troubleshoot the stator and regulator, and charged the battery too. The regulator seems to have the proper diode readings (around the low 500's) and doesn't have a short between positive/negative. But it does not seem to be charging the battery, I have to rev up the engine pretty high to even get a 13-volt reading at the battery. The stator does have an AC voltage output on all three circuits, around 23v at idle, and it just goes up from there with higher rpm's. However, the manual calls for around .5 to .6 ohms of resistance. The stator has a resistance reading of around 1.5 ohms on all three circuits. Could that be the reason the bike isn't charging? Or could it just be a bad regulator since the stator does seem to have AC voltage going out? Any help would be appreciated! By the way, I have a regulator coming in that I ordered on ebay for $25. I would like some opinions before spending the money on a new stator, those seem pricey.
 

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Thanks Nick! I'll go through those steps and report my findings. I'm very curious about how big of an effect it would have from the stator having a resistance of 1.5 ohms, since the manual calls for about .6 ohms.
 

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.......i'm not much help with electrics so.if you have a rectifier ordered try that and see if it works. in the video he has .6 ohms where your more than twice that at 1.5..I dont knowwhat effect that would have on output. he says at idle it should put out 16 volts.and go up with rpms.what may be important is the same reading across all three poles. but why so much resistance.
 

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When you are measuring resistances that low the resistance of your meter's test leads may be significant. Connect those test leads together, and you might see a few tenths resistance. Check the three stator leads in all combinations, and they should be quite close. Make sure to measure from any or all to ground, and you should see infinite resistance (no continuity). If you are getting approximately equal AC voltage across all combinations of the stator wires, chances are the stator is good.
 
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