KZ1000 running rough and misfiring

I just bought a 1977 KZ1000 and it ran great on the drive home. The guy I bought it from just had the carbs re-jetted. Now the carbs are leaking and the bike is running rough and misfiring. The spark plugs are fouled with black sooty carbon. I put new plugs in and it ran great, only for a day or so. Checked the plugs and they were fouled again. I`m thinking the points or condensers are bad or the carbs are running rich. I am a novice to motorcycle mechanics so I need some help. And also not alot of cash since I just bought the bike. Any ideas would be greatly appreciated.

Did you ask why he had it re-jetted? Does it have the stock air box and air filter? I suggest you get the Kawasaki Service Manual and perform a full tune-up. Don't expect a previous owner to have taken care of the bike at all. If you do a full tune-up and perform all the normal maintenance described in the manual you will set a base-line from which to work. Ed

Thanks for the advice. I have a Clymer repair manual that came with the bike. He didn`t tell me why it was re-jetted. (and I didn`t know any better to ask)The air filters are the pod type ones, not stock. I looked at the manual and I think I will start by cleaning the points and setting the gap and timing. The previous owner did mention that his mechanic did suggest a new electronic ignition.

Hi woodman, I too am a novice, and am going through a similar issue.

You should try and get a factory service manual from kawasaki. I downloaded one off this site. Its not my model exactly, but it is close.

You are running rich, and there are a bunch of things to look at as to why this is happening. My issue seems to revolve around a stuck float due to a lack of fuel filter. Do you have an inline fuel filter on your bike? You could easily have a stuck float... dirty carb etc... If it was running great, and now its not... start with the simple stuff first before adjusting timing etc.

Makes sense, I do have leaky carbs. So a stuck float could be it. I do have inline filters. I will start by taking the carbs off and cleaning them. Thanks for your help.

Pull the carbs take a look in the bowls clean em if necessary. Clean the pilots and look see at the size of the main jets and pilots. Post the jet sizes lets see what you got , a lot of people over jet. Be careful installing everything just snug em up. Don't strip the threads
Another thing to look at are the plug wires. If original coils there old but usually good. On all the old bikes I get I pull the plug end(cap) off and snip off about 1/4 inch of the plug wire. You'll notice it's wallowed out. Screw cap on again until snug. You'd be surprised how much better spark you get. Get new sparky plugs there cheap

Good Luck
Gregz
also know as the idiot

Thanks Greg. I will start with the carbs, give them a good cleaning and will let you know the jet size. Just before the bike started to act up, I did clean out the gas tank (it had the remain of a tank liner and was coated in rust). I used acetone to remove the liner and Metal Rescue to get rid of the rust. The tank came out clean and rust free. I rinsed it out with gas. After it started acting up I took the tank off and drained the gas and found maybe a teaspoon of Metal Rescue still remained in the tank. I am thinking that the metal rescue might have got in the carbs and gummed them up. I will post how things go. I will let you know the jet size as well

the jets are 117.5 . I cleaned the carbs and adjusted the floats to the factory height ( no more leaky carbs) put new spark plugs in and the bike ran well. Ckecked the plugs and they were black and sooty again. Still running rich.

Do you have a Header on this bike? Is the bike running rich at mid throttle or top end?

No header on the bike. How do you know when it is running rich? :huh: It was stumbling in the low end to mid-range. Thanks

Took the bike out for a spin. It runs well up to the 1/4 throttle, between 1/4 and 3/4 it hesitates. After 3/4 it takes off like a shot and runs great. Does this mean I have to adjust the needle jet and the jet needle? The bike has a high idle 1500-2000 rpm, I am going to try and adjust this down to 1000 with the idle adjustment. should I adjust the pilot adjusting screw as well? :huh:

Get a Kawasaki service manual. The Clymer is too generic. Invest in a good reference THEN proceed. You are asking for subliminal issues trying to do otherwise. My 2cents of common sense and learning the hard way.