The rectifier regulator is not involved engine with missing problems. Its sole purpose is to charge the battery and nothing else. You could disable the charging system and the quad will run off the battery just fine (until the battery eventually goes dead).

 

Well, it converts the voltage from AC to DC right...
And then it splits and regulates the voltage passing through it...

So, if the voltage were too low coming out, it would run fine while battery voltage was up. But I'd drain the battery during riding and it would die. That I understand.

If it's not regulating the voltage down enough, then it would over charge and cause my battery not to hold a charge and die while sitting... which it has done a couple times.

But I don't understand what effect high voltage would have on how a fuel injected bike runs. That's why it became a suspect.


Now I am starting to suspect the ECU, crankshaft sensor and air intake sensors.

 

Well, I couldn't test the air sensors myself, so I jumped right to the crankshaft sensor.

I think I've found the culprit of my problem right there. It does not pass it's resistance inspection with any meter and they all read close to the same.

That being bad would also more accurately line up with the symptoms I'm having too. It's still sending it's signal to the ECU, which is why I don't have a trouble light, but it's probably not sending exactly right.

Since the ECU uses it's signals to set and advance timing, ignite spark and in part to meter the fuel... I'd say all of them are off a bit, which explains my symptoms with the bike.