Help Diagnosing extremely high idle

Hello out there!

Fist post for a long time lurker. So I've got myself my second 79 KZ650, I couldn't bring my other one with me on the move and found another one while looking for another motorcycle. 1300 for 2 complete bikes, I think I did . . . ok.

But, onto the good stuff. So I got one running! Big accomplishment for me, and done with lots of help from y'all and the problems you faced. So I got her to start but once she starts she revs up real high, with the choke off. Any idea what the deal is?

I've got two videos to help try and diagnose the problem.

Links below:
1-
2-https://www.youtube.com/watch?v=kMDgpfHEr6g

Any thoughts?

Thanks!
tw

Congrats on the bikes.
I would suggest that you make sure the choke/enricher is closing all the way. I would then check to make sure the throttle cables are adjusted corrected and well lubed. After that I would check the timing advance mechanism to make sure the weights are moving freely, and of course, well lubed. The Kawasaki service manual has a maintenance schedule/check list that should be gone through completely. It will eliminate most issues.
Nice buy and good luck.

I haven't been able to find a FSM for her yet. I've got a Clymer's in VA but from what I've read there are some discrepancies.

I keep seeing digital formats for the bikes for sale on ebay but am unsure about buying one. Anyone have any experience in buying digital FSMs?

Thanks,
tw

I also believe it might be a vacuum leak. I would start checking that first.

IMHO using starter fluid or propane isn't the best way to test. The best thing to use is carb cleaner. The reason is rather than the engine revving up, which could be caused by something else, carb cleaner will cause the engine to immediately idle down and/or die if there is a carb holder leak. The key is to temporarily set the idle as low as possible while conducting the test. That causes max vacuum at the carb holders and makes the engine quite sensitive to the carb cleaner. Also, unlike some stuff folks use, like WD40, carb cleaner leaves no residue. Ed

I just figured he had a problem with a vacuum leak and hate typing one letter at a time so looked for a video. I will just stay quiet as usual

It seems there's a vacuum leak. I just replaced the air inlet ducts from the airbox to the carb. Seems the carb holders need to be replaced as well. Just scored a sec off of ebay for 73.00.

I will go through the other items while those are on the way. Thanks everyone!

peter1958 wrote: I just figured he had a problem with a vacuum leak and hate typing one letter at a time so looked for a video. I will just stay quiet as usual

:laugh: :laugh: I hope i didn't come off as being too critical; the video was fine. Sounds like you nailed the issue - carb holder leak. Ed

Thanks, Pete!

The video was a big help, and I'll bet it'll help plenty others with similar issues.

Only downside is when old videos and photos get taken down leaving the thread bare for the future.

Thanks again to all!