Ahh....boys come get Dad, bikes down again. Battery still has volts, but no amps left, so its not the battery, has to be rectifier or stator.
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I calculate the power draw..the Dyna2000 uses 2.2ohm coils, I had been using 3.0ohm coils,
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Ok. Hold on here. What GPz1100 do you have? It is the 81, 82, or 83-85?
In any case, all of the 81-85 GPz1100 wiring diagrams do show a 30A main fuse. But the manuals also show that the OE coils have a primary resistance of 1.8 to 2.8 ohms, which is pretty much what I'd expect the Dyna 2.2 ohm coils to measure. These coils do not use any ballast resistors. Also, the 1981 model has a secondary fuse that feeds these two ~2.2 ohm coils using a 10A fuse. This 10A fuse is shared with both the coils and tail light circuit.
The Dyna 2000 manual says "An innovative dwell control scheme maximizes spark energy all the way to 16k RPM. They Dyna 2000 can be used with 2.2 ohm or 3 ohm stock coils. For maximum high RPM energy, use the Dyna DC4-1 gray coils."
The mention of the "dwell control scheme" here is key. Once the ignition is computer controlled, you can do some fancy thing with the coil dwell time (the amount of time the coil in energize, or charging). The computer can leave the coil completely off until the motor starts to turn, so the coils draw zero power when the bike is first keyed on. But more importantly, the computer can chose to do a similar thing while the bike is running, and wait to energize each coil at just the right time to allow it to fully charge before the spark plug fires. This would draw much less
average current that the simple voltage and resistance calculation, since the coil spends a good part of the time unpowered. Given that the stock ignition used roughly 2.2 ohm coils, I'm guessing that the stock electronic ignition was also smart about how it controlled the dwell time.
I'm guessing the Dyna 2000 is optimized for the 2.2 ohm coils. Those are the coils that shipping with the full Dyna 2000 kit. I would not add ballast resistors to the system, as it was not designed to be used with one.
If you have the 3 ohm coils, the Dyna manual says those will also work. Even if the Dyna 2000 is optimize for the 2.2 ohm, it's likely that you'll still have full spark at the modest 8500 RPM redline of the 1100.
Here is a second thing.
Battery still has volts, but no amps left, so its not the battery, has to be rectifier or stator.
That doesn't seem right to me. The charging system (rectifier and stator) can put out a maximum amount of current. If the total current used by the bike electronics is more than the output of the charging system, that extra current is drawn out of the battery. If you run like this for long enough, the battery will discharge, the voltage will drop, and eventually the bike will stop running. At that point, the battery should read low voltage. It shouldn't want to start or run without a jump start or plenty of time on the charger. The charging system may get pretty hot along the way, but the end result is same (dead battery). If the charging system is not performing well, that would just cause the battery to discharge faster. If your battery has volts, I don't think your problem is in the charging system.
I would say that the battery/charging/rectifier/stator system is unlikely to have anything to do with the fact that you are blowing the main fuse.
I would also guess that the 2.2 ohm coils with the Dyna 2000, if properly connected,
should not be causing the fuse to blow.
If you can confirm that your bike was original equipped with a 30A main fuse, I would put the 30A in. But I would also look very hard for any wiring faults or faulty devices that could be drawing excessive current.
For example, the turn signal canceling unit on my '78 Z1R had failed, and it blew the main 20A fuse several times. But mostly the bike ran fine. I happened to remove the box from the mounting bracket and found the back of the box melted. I couldn't see any damage unti l removed it. Once I replaced the box I never blew another fuse.