battery eliminated

If the 750 is complete restore it.
Steve

Nerdy wrote:

Jason Johnson wrote: oops sorry neardy called you wrong name

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See I really am new to this technology stuff

No worries - stuff happens, and we were all new at some point.

Speaking of which, be sure to pop on over to the New Members area ( kzrider.com/forum/10-new-members ) and introduce yourself. :-)

:lol: ...I worry about getting old and stuffy.

Nice job!

I've been advocating batteryless for years. I went batteryless on my 550 about 10 years ago. I just added a capacitor, and hardwired the sense line to the output. That's the only other must-do for going batteryless if the bike has a sense line. Your 1978 Kz650 did not have a sense line originally, so it should not be an issue.

Like Ed said, some Kz's, like the 1977 Kz650 can't go batteryless. But the ones with permanent magnet alternators, like your 1978 Kz650, can go batteryless.

The one-kick only warning comes from a misconception about capacitors. People don't realize the capacitor is most likely totatlly drained before you ever start kicking. The energy comes from the alternator, during the kick, to charge the cap and power the ignition.

I'm curious, though, does your bike start with the headlight turned on? I have to turn off the headlights (i have two 55 watt bulbs, almost double from stock)) in order to start the bike.

All I know about the subject is a 1978 KZ650 with factory reg/rectifier will not regulate without a battery there as a load. I found this out years ago when a battery terminal broke off my battery. I was riding along and noticed my turn signals would no longer flash, then noticed my headlight was burned out. I burned every single bulb that was illuminated. The volts went up to stratosphere. Don't know how high, but it cost me a headlight and at least 15 other bulbs. So if you do go batteryless be sure you know it won't burn up other things.

RonKZ650 wrote: All I know about the subject is a 1978 KZ650 with factory reg/rectifier will not regulate without a battery there as a load. I found this out years ago when a battery terminal broke off my battery. I was riding along and noticed my turn signals would no longer flash, then noticed my headlight was burned out. I burned every single bulb that was illuminated. The volts went up to stratosphere. Don't know how high, but it cost me a headlight and at least 15 other bulbs. So if you do go batteryless be sure you know it won't burn up other things.

Yes, that is true, but as long as a capacitor is there, the regulator should work ok. But it is worth mentioning that you really want to make sure you have a good, reliable capacitor, or you can run into trouble.

The battery doesn't need to act as a load, but it does need to smooth the pulses. The regulator is designed to regulate the average voltage. But if the voltage is in pulses, the RMS voltage will be too high and cook everything.

When you lose the battery or capacitor, the DC voltage has a huge AC component due to the pulsing. The AC component contributes a much higher RMS voltage. With smooth DC, the RMS voltage is close to, or exactly, the same as the average voltage.

It's much more difficult to regulate or even measure RMS voltage, and bikes usually only need to deal with average voltage. RMS is the true measure of the energy carrying capacity of a signal. But with pure DC, the average voltage and RMS voltage are the same, so regulators usually regulate average voltage. It's only when the signal has large fluctuations that the RMS and average values diverge.