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Just happening to be looking at my service manual. On my bike there is a starter relay. And in thought of your issue.

1) Does your bike have one?
2) If yes, have you checked it?
3) Have you check the fuse box for any gremlins in there?

Ride Smart! Ride Often!
 

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^ thats kinda the line I was thinking, in a car the ECM does not tell the alternator to output voltage until the car is started and the starter has been released

I wonder if the ECM tells the voltage regulator to stand down while the bike is being started. If that output has failed or is weak, it may not be enabling the regulator after the bike has started.

I have not dug into the schematics for any of my bikes to see how this works. Its difficult to analyse the yamaha schematics, because they show how all the components and modules are wired together, but the modules are shown as black boxes on the schematics, with no indication of what each wire and signal is doing, or how it works inside the modules.

Having said that, it would be useful to go thru the service manual debug tree for "battery not charging" and see what actions it recommends.
 

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Just went back to your first post and noticed this:

Stator unplugged n it puts out 60+ ACV all day long..
Plugged in n it drops to 11 ACV n only 12.4v or so at battery..
if the stator is generating 60VAC on all three phases, and it drops to 11 VAC when the stator is plugged in, but its not sending any real power to the battery
then the regulator is loading up the stator and pulling the voltage down below the battery voltage.

I cant believe that is how the regulator works - they did that on the first goldwings, they put an alternator in that output 15 something volts, and to reduce the voltage they loaded up the alternator with a dead load to drop the voltage... Those early goldwings all blew out their alternators, and you had to take the engine apart to replace them.

Unless the service manual has a debug tree for this I would want to see what a working bike does to the stator voltage when the regulator is connected and unconnected.

It also makes me wonder if someone buggered up the wire harness somehow, and the stator wires are mixed up with the ground wires, or some other stupid mistake. It left the bike in a condition where it was sorta charging the battery, so whoever did that before you got your hands on the bike just left it that way?

One of the assumptions we always make when debugging electrical stuff is that no one has been in there changing wires or connectors around - we assume something has failed, and when we replace it, it will work correctly.

For example, if the regulator has an input connector, and an output connector, and the previous owner swapped one for the other, I would never know which one is which on the regulator....

or maybe they put a regulator from another bike in, and changed the wires on the connector to match...
 

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Discussion Starter #24
Lol where to start..
ECM does not control any of the charging on this bike
Yes there's a starter relay n yes the engineers ran the charging line through it ., it has been checked multiple times n shows good
Bikes shunts the excess voltage off through heat at the regulator.
Battery full or not it should always show 14v+ while revving bike.. Usually they level out around 14.5-14.8v...
Bikes out of my garage now so can't waste anymore time on it.. I hate that it left not 100% but customer is going home till next year n it definitely wasn't gonna sit here for a year..
 

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Discussion Starter #26
Sucks not know what the cause & fix was.

Hudging by what you did. I'd put money on the issue was someone moved wires around.

Ride Smart! Ride Often!
Yep I hate it left not 100%..
His buddy just dropped off a vstar 650 that has sat for 9yrs (wife passed away in 11 n now he's gonna get it out n ride it)
 
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