GPZ750 Starting Problem

82 GPz750. I put the carb rack back on my bike after another cleaning session and stting fuel levels. I also pulled the valve cover and checked clearnances.

When I press the starter button, the starter turns the engine over for a few seconds, but then I hear what I can best describe as a rattling/spinnning noise from the starter/middle engine area. I have the ignition cover off, and noticed that when the noise happens the shaft stops spinning. If I keep trying to start it, the same thing repeats. The engine will not start and has a couple of pops every once in awhile from the exhaust. I'm looking for some insight and where to start.
Thanks
Nick

sounds like a starter clutch problem.

The starter clutch unit is over spinning the crank. It probly could use some inspection/maintenence. The parts are very inexpensive to replace and its not a difficult job either. You will need the manual.

You could remove the air filter and spray some quick start in there, as the bike should start and run fine after just a couple revolutions.

Good Luck.

My KZ650B2 has same problem. I have replaced the starter with a used one and the problem did not go away. How long would you estimate it would take to fix the problem. There is only about 1 month left of riding weather here, so I am debating to fix it now or make it a winter project?

I'd suggest going to www.kz650.info and read up on starter clutch replacement. Over at www.kawasakimotorcycle.org a member "kopcycle" recommends pulling the engine to be able to work on it as trying to do it in the frame can be tricky.

Thanks:
I looked this up in my KZ650 service manual, and I would agree that it would be easier with the engine out. My Clymer manual was useless on this topic.
I think I will wait until something else needs fixing before I tackle this. Got to love kick starters!!!!!

Not going to help the original poster.... He has no kick starter. If I wasn't considering putting the original motor back in my bike I would offer my spare. Sorry... It's 99% the starter clutch problem tough from the description.

I tore into it today and I just about have the starter clutch out. The big question now is what needs to be fixed with it, or what do I need to test or look for?
Thanks
Nick

Well I got the secondary shaft and starter clutch out tonight. According to the parts diagram, it looks like springs, rollers, and pins are the parts that can be replaced. Outside of replacing these parts, is there anything else involved with servicing the starter clutch?
Thanks
Nick

Check the shaft the rollers ride on for smoothness, you don't want any rough areas or "Burrs" as this might make the starter clutch hard to dis-engage.

Thanks. I disassembled the unit. From playing with it a little, it seems the spring tension should be stronger.
Nick

Springs can loose some of their tension due to overheating,I'd order new parts and re-assemble the engine.