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Discussion Starter #1
I purchased a new stator last year and just got around to putting it back on this year. I rode the bike for a little while but found that I am getting pretty crappy voltage. Around 12.5-13 in all RPM's. Here's the kicker -
1. I checked AC voltage between stator wires, all were around 60V at 3k RPM's
2. I checked stator wires to ground, continuity alarm went off for all of them.

It appears by stator is grounded, but it's still pushing out proper voltage? Not quite sure what to do at this point since it's basically a brand new stator with only about 8 hours of cruising on the bike so far.
 

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Something isn't right.

Were the stator leads disconnected when you did the ground test?
 

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Discussion Starter #3
Something isn't right.

Were the stator leads disconnected when you did the ground test?
Yes, the three yellow leads from the stator were disconnected and the bike off when testing ground. I tested against the metal of the engine and the negative battery terminal and both times it rang for continuity.

I'm almost positive the r/r is bad, so I just ordered a mosfet one off of eBay (used fz09 with the plug kit).

I rode for probably 2 hours today and the bikes voltage with bike off was 12.81V at beginning of day to 12.60 at the end.
 

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I don't see how you got 60vac with all three legs shorted to ground though.
 

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Discussion Starter #5
I don't see how you got 60vac with all three legs shorted to ground though.
Yeah I'm honestly not sure. At first I thought it must be a mistake, but the alarm goes off right away from any of the three terminals. And I made sure the voltmeter was set to AC, and consistently got 50-60V when revving.
 

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It's exactly as you said, and still confusing about the continuity tone. I can't explain it, there may be some reason the audible can't be used. If all three legs had a path to ground, I don't think it would put out any AC volts or very little.

I was hoping to see the ground test with ohms instead of the audible, I wasn't clear on that. :) The norm is for the meter to show OL for open loop. As good as the other readings are, I would expect to see OL when using the ohms setting. If you get the OL on all three legs, your stator is perfect.
 

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Discussion Starter #10
It's exactly as you said, and still confusing about the continuity tone. I can't explain it, there may be some reason the audible can't be used. If all three legs had a path to ground, I don't think it would put out any AC volts or very little.

I was hoping to see the ground test with ohms instead of the audible, I wasn't clear on that. :) The norm is for the meter to show OL for open loop. As good as the other readings are, I would expect to see OL when using the ohms setting. If you get the OL on all three legs, your stator is perfect.
Ah, sorry about that! So I just tried using the ohm readings to go from stator wire to ground and they came up around 1.3-1.5 ohms.
 

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Electrically that’s not supposed to be, the regulator is the path to ground with these two parts. The stator should be isolated so the juice outputted can be put back into the system. By it being grounded the voltage basically wasted.
 

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....

I just tried using the ohm readings to go from stator wire to ground and they came up around 1.3-1.5 ohms.
That's no good.

Has this meter ever lied to you?
 

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Discussion Starter #13
Electrically that’s not supposed to be, the regulator is the path to ground with these two parts. The stator should be isolated so the juice outputted can be put back into the system. By it being grounded the voltage basically wasted.
Shoot, so guessing that it's reading good voltage, but with it being grounded it's wasting that voltage that I'm reading? So basically, new stator time?

That's no good.

Has this meter ever lied to you?
No, not that I know of at least. :frown2:
 

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Does your bike have the stator plate mod? I’m just thinking of ways it could be shorted. Did it ever work right? Meaning did it put out the correct VDC?
 

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Discussion Starter #15
Does your bike have the stator plate mod? I’m just thinking of ways it could be shorted. Did it ever work right? Meaning did it put out the correct VDC?
I bought it from my coworker and it had a bad stator. No tuxedo mod, just pulled the engine and put it in manually. I had a crappy r/r that I purchased though which I'm guessing caused the issue. I just purchased a MOSFET one and have a spare stator from a spare engine that I purchased.
 

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The voltage between two legs of the stator is determined by the how many windings are between them. What they DONT care about is if other chunks of metal are touching the windings at points in the middle (which is just a multi-tap transformer). So, a stator shorted to the housing (not shorted between windings) will still produce AC voltage between the legs even if there is contact between the windings and the stator body.

I bet if you check for AC current between the unplugged stator leads and the engine you'll see at least 20v when revving.

Which brings us to the rectifier. Once the rectifier is plugged in to the stator, it adds a SECOND path to the engine via the wire to the negative battery terminal. The voltage that would normally be forced "backwards" through the battery to charge it can now avoid the battery and flow directly back to the short in the stator windings. I don't know exactly what that would look like as far as voltages is concerned, but it's definitely mixing the AC and DC side of the rectification circuit, which is not good.

Since the ohm readings between the leads and ground are practically the same for each lead, it may be the center splice of the windings may be shorting to the stator body. If so, it may be possible to fix the stator by adding insulation between those two electrical components without having to rewind/buy a new one. Still a PITA though.
 

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Discussion Starter #18 (Edited)
The voltage between two legs of the stator is determined by the how many windings are between them. What they DONT care about is if other chunks of metal are touching the windings at points in the middle (which is just a multi-tap transformer). So, a stator shorted to the housing (not shorted between windings) will still produce AC voltage between the legs even if there is contact between the windings and the stator body.

I bet if you check for AC current between the unplugged stator leads and the engine you'll see at least 20v when revving.

Which brings us to the rectifier. Once the rectifier is plugged in to the stator, it adds a SECOND path to the engine via the wire to the negative battery terminal. The voltage that would normally be forced "backwards" through the battery to charge it can now avoid the battery and flow directly back to the short in the stator windings. I don't know exactly what that would look like as far as voltages is concerned, but it's definitely mixing the AC and DC side of the rectification circuit, which is not good.

Since the ohm readings between the leads and ground are practically the same for each lead, it may be the center splice of the windings may be shorting to the stator body. If so, it may be possible to fix the stator by adding insulation between those two electrical components without having to rewind/buy a new one. Still a PITA though.
Ah, that makes much more sense. So it's putting out voltage, but basically since it has another ground lead it can "leak" out the actual voltage doesn't get to the battery. I have a spare stator from a spare engine I bought, and I just bought a MOSFET r/r, so I'm going to take a weekend and get everything hooked up. Thanks!
 

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That’s what I was getting at in my first post. If you look at an electrical diagram of the two components. The stator does not go to ground directly but through the rectifier. Here’s a basic schematic that shows that.
 

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I wonder - If you could mount the stator so it's insulated from the engine, would it still work if the windings contacted the core?
 
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