1977 kz650c1 not charging?

hello all.. im new here

i recently purchased a 77 kz650c1 the bike ran fine for a few days, but now it seems like its not charging. the bike wont kickstart, and it seems to have drained the battery on the last ride i took it on. if jumper cables are hooked up to it it starts fine and continues to run for ~10 seconds after theyre removed. the battery has around 10 volts in it.


i first assumed that i had a bad battery.. but if this were the case wouldnt the bike kickstart without any problems? i assume so.. anddddd it def. wont

all the fuses are good and making contact..


im not terribly familiar with bikes.. more so with cars but from what i understand they have a "Stator" which, esentially does the same job. could this be my problem?


any help would be greatly appreciated

i will try and help here



first things first... check and make sure the battery is good and doesnt have a dead cell! you can get one of those nifty eye dropper deals or take it to get load tested!

next check and see how much your stator is putin out by getting a multimeter and turning it to AC and puting your leads on the connectors should get around 20+ AC at idle and 70+ at 4000rpm


i was going throught the same shit and it was my battery!

other folks will give you a better explination on things!

you are going to need to charge the battery fully, the bike cannot recharge a dead battery, you need to get the battery load tested also.
after you get the battery sorted out, put a meter across the battery with the bike running at about 3000 rpm, read the voltage to see if it is charging

Heres how your charging system works.. First the stator makes A.C power, then the rectifier changes the A.C to D.C, then the regulator regulates how much power the bike is to recieve. So, your bike could be doing what mine was and that is overcharging the batt. causing the fluid to overflow and then the bike dies! An empty batt. cannot carry voltage. Things it could be are a bad regulator,or rectifier but I have a fealing its a bad regulator. I hope this helps some as I am a rookie also!!

thanks a lot guys... the battery did seem unusually warm when i took it out of the bike


also the thing thats puzzling me is that i cant kick start the bike... it would seen that battery charged or not the bike SHOULD kick start.. however.. it seems on my bike that someone has done some creative wiring and ran the hot wire for the coil directly from the battery terminal.. which would explain why the bike wouldnt kick start if the battery were dead/missing


thanks for the help guys.. im off to see if the battery will take a charge.. if so ill post back up with what kinda voltage the battery is recieving with the bike running



thanks again!

You want to rewire your coils so they are not powered all the time. Look in the Filebase for the Coil rewire mod.

ok guys so i charged the battery... standing alone it had almost 13 volts in it


in the bike after trying a little to start it it has a solid 12.3V

with the bike running at idle its at 12.3 ish...


at around 4500rpms it was 12.6v

so obviously the charging system is not right..... its also pretty obvious the bike is generally starved for a strong electrical source.. the idle sort of wanders when you apply the brakes and the plugs are black ( as if its not getting a strong enough spark to burn the fuel completely)


i would assume it is the stator.. it doesnt seem likely that a regulator would go bad and still regulate.. too much so hah



if anyone can speculate (i wont be able to get to it till later on this weekend) what would be more likely to cause the problem?

and how much can i expect to pay for a regulator and a stator?


thanks a lot guys!

ill look into the coil rewire OKC_Kent thanks!

Post edited by: claytonsmith, at: 2007/06/09 02:51

It still could be the regulator /rectifier, but you would be better off starting of with a manual and going through the proper diagnostic steps to verify, stators can be very pricey BTW you should have atleast 1 volt over battery voltage at rpm, last I checked reg/rec units ran about 60.00 usd

katjbus wrote:

It still could be the regulator /rectifier, but you would be better off starting of with a manual and going through the proper diagnostic steps to verify....

Concur with above.

If replacement is necessary, would consider a new combo unit from Z1E:

reg/rec combo unit from Z1E

Good luck with the repairs.

And might want to also check this link

good info

And yet another


more good info

if you have the true 77 charging system then the reg. can be fixed, I would get a book and follow the test to see what is thr real problem.