TOPIC:

Ok so it's been years since I've been on here with a different bike. I now have a 1978 650b. I just finished tearing the carbs completely down and dip cleaning them and put rebuild kits in. I put new coils on it (I was getting bad ohm readings on one of them), blew out every passage in the carbs I could find. I hooked everything back up, and am having issues when I give throttle it wants to die upon initial turning of the throttle. I checked voltage at the coils and am getting 9.??volts at coil. Also when running at idle I am getting a 12.48volt reading at the battery. First of I should be getting 12volts into the coils and am not. Also I'm pretty sure I read on here that with the motor running I should be getting close to 14volts at the battery, and am not. The bike will idle at 1000ish rpm, but once I give throttle it will bog if not die, unless I slowly give throttle. If anyone has a quick fix that'd be great! Thank you!

Is the ignition stock?

When you measure the voltage, where are you putting the meter leads? If you are measuring the negative side of the coil, while running, you will get a very low reading.

And do you have a manual? You could try the open-load stator test, but it sounds more like you are losing voltage in the system somewhere if you are measuring the positive side of the coils to ground. In that case, I would look to clean up the fuse holders first, then check switches and connections.

Yes ignition is stock. As far as when I measured coil voltage, I just turned the key on and measured voltage, which now that I type that I just remembered my battery is low, duh.... I'll measure what my battery reading is when I get home and measure coil voltage again. I am measuring positive side of coil..... As far as the 12.49 reading on the battery when running isn't that too low? I have the 77 manual

That type of alternator does not put out much power at idle, and if the battery is really low, it can drag the voltage down. If revving up gets it above 13.5, then it'll probably be ok after the battery is replaced and/or charged.

Thank you! Ok so I came home tonight and rechecked voltage readings, so while reving voltage at battery is good, reading 13.??V..... I did re check voltage at the coil and still reading 9.??V. I'm really not sure if this is even causing my issues, but I do know that I cannot get my carbs tuned without encountering issues. One quick question outside the electrical realm, stock main jet is I think the manual says 100. The old main jet and the new main jet are 102. Is this going to cause issues?

The main jet is not 100; it is 102.5. See B2 on chart below. Ed

Well seriously the service manual says 100.. I'd post a pic but not sure how to from my phone.....

So if not getting 12v at coil + what would solutions be?

Clean contacts or install a relay. I installed one to bypass my 40 year old wiring.
Steve

twfields79 wrote: “Well seriously the service manual says 100.. I'd post a pic but not sure how to from my phone.....”

I don't know what manual you are using, but I respectfully suggest you toss it out and buy a Kawasaki Service Manual for your specific year / model bike. Here is an image from the Kawasaki Service Manual. If your manual shows a 100 main, the manual is junk. Ed

So do you have any info on installing the relay?

Check your contacts and connections first. I'll dig it up later or someone here will post it.
Steve