voltage drop on a 93 zx-7

[slydman]

I have a 93 zx-7 and at the end of last season I started to have a problem with starting. I would have to jump start the bike and after an hour ride i could not get it started. Each time i wanted to ride i would hae to either jump start it or pop start it. I replaced the battery and still have the same problem. so I'm having the same problem this year. I broke out the DMM and tested the battery and it ready 12.6 volts but when i turn on the key it drops down to about 8 volts. Any help with this problem would be appreciated thank you.

[MFolks]

ElectroSport - Motorcycle, Dirt Bike and ATV - OEM Quality Stators, Regulator/rectifiers and CDIs has a good troubleshooting page for battery charging problems. I'm familiar with the older Kawasaki's having the magnetic rotors, so can only offer advise on your charging system woes.

Some Kawasaki's have a smaller automotive alternator charging the battery, and others have a belt driven alternator(maybe your belt if you have one is slipping?).

[sfair]

Battery appears to be bad or dead. The first step would be to charge it up and do your voltage test (key off and on) again. If the battery will not hold over about 12.4v, key on for 5 minutes, then you should get it load tested to be sure.
If you replace the battery or it does hold, then do a charging system voltage check. Post back if you need any help with that.

Post back with your results.

[slydman]

Battery appears to be bad or dead. The first step would be to charge it up and do your voltage test (key off and on) again. If the battery will not hold over about 12.4v, key on for 5 minutes, then you should get it load tested to be sure.
If you replace the battery or it does hold, then do a charging system voltage check. Post back if you need any help with that.

Post back with your results.

i checked the voltage in the charging system and it charges at 13.96 at idle and about 16 at 100 rpms. thanks i'll get battery checked

[sfair]

about 16 at 100 rpms.

16 at 100????
Could you take that voltage measurement again and post back?

[slydman]

16 at 100????
Could you take that voltage measurement again and post back?

Sorry about that 16 volts at 3100 rpms

[sfair]

It seems that your charging voltage is too high, and that will shorten the life of your battery.
Go to the site that mfolks listed and do some regulator/rectifier troubleshooting.

If you have any problems or questions, post back.