82 750 Spectre issues

Hi all, I'm new to the forum as I just bought my first bike, a 1982 kz750 Spectre. It was my friend's grandfather's bike and it only has 2700 miles on it. I have put it a new air filter, plugs, battery and cleaned the carbs. it starts right up, idles fine (since I have adjusted the knob under the carbs) until it warms up...then disaster strikes. White smoke begins pouring from the exhaust, primarily on the right side (looking at it from the rear) and black fluid is leaking from the mid-section joint and tip of that side's exhaust. It is at this point when the motor begins to rev itself to about 4000rpm and will continue to smoke. I'm sort of lost at this point, could anyone offer me some advice? Thanks in advance guys!

Apologies, I forgot to mention that I occasionally see fuel leaking from the overflow hoses on the carbs and have checked for potential vacuum leaks everywhere possible with no luck....sorry

Hello, Rob, and WELCOME to KZr!

If oil and filter haven't been changed, would sniff-test the oil and examine its physical condition, in order to determine whether it's fuel contaminated.

Good Fortune!

Thanks for the tip Patton, I did change the oil and filter (filthy) but I did not smell any fuel. I am leaning towards a vacuum leak somewhere but wasn't sure if there was something else that I might be missing? Thanks for you help, I appreciate it.

Unscrew the oil fil cap & do a "Sniff Test", if it smells like gasoline, DO NOT RUN THE ENGINE ANYMORE WITHOUT FIRST CHANGING THE OIL, AND THEN FIND OUT WHY THE CARBS/PETCOCK LEAKS!

A vacuum leak can cause the rpm's to climb, The rubber boots(from the air filter box to the carbs), and the carb holders(between the carbs and engine)can go bad from sunlight and solvent exposure. www.z1enterprises.com should have what you'll need.

To check for a leak, use an UNLIT propane torch around the above mentioned parts while the bike is at idle. If the rpm goes up, you've got a leak or two. Check the 4 rubber sync plugs on the carb holders for cracking too, along with any vacuum lines.

Check the mechanical ignition advancer(behind a CD sized cover on the right side of the engine)with the engine off, give the advancer a twist, it should return to it's position with a snap, if it's sticking, make note of how it's assembled, as it can be re-assembled 180 degree's out. Remove it & clean and oil the moving parts. 3-in-one or sewing machine oil is about all it needs now and then.

After warm and white smoke begins pouring from the exhaust, does application of choke have any effect?

If not already done, would also assure that the timing advancer is properly functioning. The advancer might need lubing.

Good Fortune!

Found 2 vacuum leaks...one on a boot attaching the air box to the carb; I repaired it. I also replaced the vacuum line attaching from, the top of the motor through the hole in the airbox to a plastic nipple inside the box. Now when I start it up it revs up really high.

When I turn the adjuster screw clockwise all the way, the bike revs up like I have it pulled to full throttle. When counterclockise, it shoots up to about 4k and holds there. What is going on here, I am totally lost!

If the epa paraphernalia is still connected, would detach its vac hoses from the carb holders, and cap/plug the vac nipples on the carb holders (see image below). This is to eliminate possible air leakage due to the epa paraphernalia.

Could also temporarily detach the vac hose from the carb or carb holder that's furnishing vacuum to the petcock, so as to eliminate possible air leakage incident to the petcock, and test run with the petcock in PRI position.

The above should leave all vac nipples capped/plugged.

If racing idle persists after warm-up, use the thumbscrew to reduce rpm to the lowest relatively steady idle, where WD40 may be sprayed around the carb holders to test for any change in rpm caused by ingestion of the WD40.

Imo, it's not the airbox hose.

Good Fortune!

I can easily run a section of vacuum line to connect the 2 nipples you have pointed out in the image on the right, but what exactly is the image circled in red that needs to be removed? What exactly is that?

Check to see if you can see the oil level in the site window. You may have over filled it. Bob

SpectreRob750 wrote: I can easily run a section of vacuum line to connect the 2 nipples you have pointed out in the image on the right, but what exactly is the image circled in red that needs to be removed? What exactly is that?

What exactly is that? --- That's the factory installed epa paraphernalia on bikes so equipped.
It's called Kawasaki Clean Air Injection System (see image below).
It's unnecessary for proper engine performance.
It serves to inject addition air into the exhaust ports to help burn any remaining fuel.

If it's there, toss it!

Good Fortune!




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