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I recently had my clutch replaced and a new battery put in. Within a month my regulator/rectifier burnt out of it. So, I purchased a new one. After 2 weeks that one burned out also. I replaced the stator, the battery again, and the wiring harness. Now, this is my 3 regulator/rectifier that had burnt out on me. After the second one, I was told to have it mounted outside of the frame. That only lasted a week and it had burnt out again. Everything I purchased was brand new, so I was wondering if someone could help me find out the problem.

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1 Answer 1

[answer in progress]

One of the reasons regulators burn out is overheating. That is why people put it outside the frame on some bikes to get better airflow around them, and out of the cooker. However, given that you had done that, it must be other reason. I would suspect connections, but then again, you had replaced the harness (seems a bit rash, replacing major parts willy-nilly).

But here is something about regulator ground (via

The biggest problem with rectifiers, and in my experience why the burn out, is the lack of a good ground to the battery. The back of the regulator is metal and is supposed to ground against the frame. After a year or two, the aluminum gets a layer of oxidation on it that makes the gound very weak. The rectifier, which uses the ground to determine battery voltage, thinks the battery is low and over charges in an attempt to get things back to normal. This usually burns out the reg or battery or both.

Running a ground wire to one of the bolts on the reg with a big round wire end that contacts the back of the reg almost always fixes the problem. As long as the system isn't too damaged. The over heating in the system also often causes the connector plug between the reg and the stator to go bad as well, so be sure to check it for melting or bad wires.

Edit: Here is another possible issue — surges or shorts in high-voltage ignition system that can fry components of low-voltage system (see answer from Burned regulator/rectifier question).

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