Electrical weirdness continues ...

[Gary]

Well, I replaced the diode on my scoot and things started to look promising. The engine now continues to run if I disconnect the battery, and the lights get brighter as I rev up the scoot. So it appears I'm getting at least some output from the stator now.

But here's the strange part. Now the scooter idles terribly. It misses and sputters and stalls almost every time. Before replacing the diode, the scooter idled flawlessly. At higher rpms the scoot still runs fine, and top end is not affected. Also, another weird thing: The turn signal clicker now won't click when the engine is running. With just the key on and the motor not running, it clicks normally, but as soon as the motor starts up, it stops clicking.

So, more Chinese puzzles. I suspect perhaps the voltage regulator is bad. I will take some measurements to try to confirm this.

Any thoughts are appreciated.
Gary

[Jacine]

Your poor idle is most likely from a poor (cold) spark. There is not enough power being sent to the spark plug to create a hot enough spark. Similar problems occur when a battery cell fails but still has enough juice to turn over the bike. The higher RPMS generate enough current to give a hot spark. Since you disconnected the battery the only power is coming off the stator (alternator) and its not enough at low rpms.

[12string]

Gary,
What does the scoot do when the battery is hooked up? Any difference?

[Gary]

The rough idle/no clicking is with the battery connected. I disconnected the battery only temporarily to see if the scooter would die (which it would before repacing the diode).

Weird huh?

[12string]

Switch the diode back. See what happens . It might be a unrelated problem. That's Chinese scoots for you put out one fire and another one starts.

[Gary]

12string -
Yes, good idea, will do. If it was just poor idle at low rpm, I might suspect that the spark plug fouled coincidentally at the same time as the diode was changed, but the turn signal clicker not sounding when the motor is running definately makes me think the issue is related to the diode. I'm going to order a new voltage regulator so I can rule that out as well.
Thanks,
Gary

[fulltimerart]

Try adjusting the idle up a bit--it takes power to put out electricity and that could be drawing your idle speed down just enuf to make it run rough. Art

[Gary]

I disconnected the diode and voilla: the idle is back to normal (smooth as silk). Strange thing is the turn signal clicker still only works when the motor is not running. Also, the lights get brighter as I increase the engine rpm. However, without the diode in, if I disconnect the battery while the scoot is running, it dies.

Art, you are right that making electricity draws power from the engine, but even if I give the engine more throtlle, with the diode in the engine runs really rough at lower rpms, like its not getting good spark.

I've got a new voltage regulator and another diode on order. Will try replacing these and see what happens.

Thanks all. Gary

[MLN]

I know this is of absolutely no help but it sounds like it is wired incorrectly.

[Gary]

Yes, another chinese puzzle.

I bought a small car battery that I carry around underseat as a spare to extend my crusing range. That's keeping me on the road for now.

[Showme]

Hi Gary, It probably won't help you, but here is what I found on my MC54. Under the instrument panel, the wiring has 12 seperate ground wires all hooked togeather in one mass and then taken back to the ground point by the battery. The wire carrying this mass is very small. I mean, very small. Three of the grounds were not even connected. Just stuck into the big bundle. I hooked the wires into groups of four on heaver wire and hooked the three wires togeather on even heaver wire. This is grounded to the front of the frame. So far my weird electrical problems have stopped. (knock on plastic, no wood handy)

[Gary]

Thanks Terry, excellent suggestion. I'll look at this.
Gary