I have a 1982 KZ750 spectra, as always been a good runner, lately it will not idle under 3500 RPM, i have done various checks and do not believe it is a fuel problem. I would like help on solving this problem, suggestions etc, Thanks

Hi William:
Here's a great article on your bike.
http://www.ridermagazine.com/manufacturer/kawasaki/retrospective-kawasaki-kz750-e-1980-1982.htm/
Cheers.

Starving for gas! check fuel tank vent. Check fuel lines. Check Fuel filter. Check fule pump. Check carbs. clean with seafoam!

I believe this can be a bad O2 sensor error. It is a lean reading on bank 1. Also what can happen are intake manifold leaks, and stuck Intake manifold runners on 1 side of the engine. For the Manifold runners, these work like a gating system. Some Intake manifolds have 2 chambers, a low and high flow. When the gating runner sticks in the high flow position, too much air enters the engine on Bank 1 during idle or low rpm.
Manifold leaks. Use a spray water bottle and with the engine running, spray the seams of the manifold. A leak will change rpm or stall the engine.
Hope this helps you.

Hi,

Hope this doesn't reach you too late. These bikes take some time to fully warm up.

You can adjust the idle down by turning the knob between the #2 and #3 carburetors counterclockwise until you reach 1050rpm. Wear a glove or you will burn your hand!

Ride the bike some more, and see if the idle stabilizes. If not, you may have a vacuum leak somewhere.

A quick way to diagnose this is to take a propane torch (NOT LIT!) and run it around the carb boots and vacuum caps. If there is a change in rpm, then inspect the boots and caps for tightness and cracks.

hav u disassembled the carbs and cleaned um in solvent-may be gummed up from age etc--ajusting jets can be done but takes proper values n knowhow cause to rich to lean can damage a motor

check for clogged fuel filter, ignition coil , distribuitor rotor

Hey pal, this bike probably sat 4 awhile right?
If your idle jet is clogged it won't idle, the carbs need to come off, turn them upside down and remove bowl to see the jetsIf this is too much then take it to a moto mech

have you checked the engine for vacume leaks or advanced timing or even sticking accelorator cable or linkage? these are always a good place to start for excess acceleration

check your fuel pressure, should be 40lbs+ at idle. If you dont know how to do this, have a friend or a shop check it for you. I had same problem, no power at all would barely run ect,, turned out to be fuel pump.