Bad Generator or Bad Battery??

Hello!

First off, I'm new to the forum as well as new to riding motorcycles! So far I'm lovin it! My dad has had a decent 81 KZ305 CSR sitting around in his garage for years now and I've recently decided to fix her up and start riding.

My main problem at this point is that my battery is not holding a charge. Bought a brand new one, charged it up and cruised around for about an hour, parked it and the next day I came out and drove it again. This time about half way out I noticed my power dropping off and when I came to a stop it simply stalled out and wouldn't start. Luckily I was able to push start it and made it most of the way back with very little power and about a block from home it finally died and refused to fire up even trying to push starting it.

If my generator is working properly, push starting should have been enough to get me home right? How can I check to see if my generator is working correctly and what can I do about it if it's not?? Parts seem to be pretty hard to find for this bike! Can you recondition generators?

As a side note, the coils for this bike were also shot and my dad rigged up a couple of universal auto coils which seem to work fine, but could they be too large for the generator to keep up with?? I'm really confused about what's going on and I've already put a couple hundred dollars into a few new parts for it (speedo/tac cluster, ignition, and new mufflers). Hoping all is not lost...

Hi SimpleCJ,

Welcome and have fun!

You need to test the charging system, first, you will need a multimeter. Get the battery charged up and install it.

Set the meter to DC volts, about 20 volts or whatever the setting over 15 volts is on the meter.

Start the bike and touch the positive and negative leads of the meter to the corresponding battery terminals. It should read about 13 or 13.5 volts at idle. Then rev the bike up to 4000 rpm and the voltage should go to about 14.3. If it does this then you're charging system is all right. If it does not check out then follow the steps in this link first.

Electrical Fault finding

Here is a link to a wiring diagram for your bike
305 Wiring Diagram

Check that the red and white wires from the regulator/rectifier are hooked up and that it goes to the positive terminal of the battery. That red/white wire is what keeps the battery charged up from the alternator. It will help to disconnect the wires (one at a time) and spray some electrical contact cleaner on them. Older bikes suffer from dirty connections.

Something else to consider is getting the fuel system cleaned up. Install a small fuel filter in the gas line between the petcock and carburretors.

Tell us what happens and post a picture or two.

Kent

Thank you so much for your help. With the wiring diagram I was able to trace out the wires and found that the wire from the rectifier was not connected. I now have charge!!

Only problem now is my carb is not working correctly. Just got two new float valves and of course they were not the right parts, right needles, not the right seat though. I had to seal the one seat with plumbing teflon tape (the other seat is original), file down the side to make room for the float hinge and bend the lever that pushes on the needle because the new seat was higher than the original. Now that side is not getting gas, possibly because the float is stuck. I hate how hard it is to find parts and then not knowing if the parts I order are actually the right parts. My float valve seats should just press into place, but all the replacement seats have threads and sit too high.

At least now I don't have to worry about my battery dying again! Thanks again for your help. I'll take some pics and post shortly!

SimpleCJ