KAWASAKI ZX 7R

When trouble-shoot a ZX7R, first start with the fundamentals. These simple trials can work for any engine. All engines need three basic things to run fuel, spark and air. These simple things can cause your Kawasaki ZX7R to not start up or run poorly.

First start off with the fuel Remove the hose off the tank and make sure the fuel is flowing properly. Some bikes will have to turn the fuel selector to prime, not on, or fuel will not flow.

Take a flashlight and look down into the tank, is the fuel varnished or is there dirt in the tank? Older Kawasaki ZX7Rs had a problem with tanks oxidizing inside and would plug the screen up inside the tank. Fuel delivery may still be a trouble but we will come back to that later.

Next Withdraw the spark plugs, you may need to Withdraw the tank to reach them. Inspect every spark plug as you take them out. All the spark plugs should look the same. If a plug looks white colored, that piston chamber may be (lean) and not getting enough fuel.

If you have a plug that looks wet and black, that piston chamber may getting too much fuel (rich) or not sparking good. Withdraw all the spark plugs and snap the plugs back into their wires.

Set the spark plugs on the engine so that they can ground themselves. Crank the motorcycle over and watch the plugs for sparks, preferably somewhere dark. Make sure you look at all the plugs to make sure they are all sparking.

If one spark looks weak check the wire and plug, if old or worn replace them. If their is no spark the coil may be bad.If you have any test equipment such as an ohm meter, you can find out what the resistance reading should be for your bikes coils.

This way you will know for sure if the coils are o.k. If the ignition system looks fine move on to the carburetors. First, if the motorcycle has not been maintained recently (a trouble in itself) make sure the carbs are synchronized. To do this you need a vacuum gauge made for this. Remove the small rubber plug located between the carbs and the piston chamber.

Attach the gauge and take the readings from each cylinder. Replace the caps when not measuring or it won't run right. Adjust the throttle screw or linkage for that carb until they all read close to one another. Refer back to inspecting the spark plugs. If one cylinder looked lean or rich check all hoses for cracks and air leaks. If the ZX7R has not been run in awhile the carbs may be (gummed up). Withdraw the float bowl off the bottom of the carb.

Look in the bowl for dark varnish looking gas. If the fuel looks dark you will probably have to Withdraw the pilot and main jets and carefully run a wire through the center hole to clean them out. Be careful to not bend the float as the peak needs to be correct to run well Also. Check that the small needle attached to the float between the pivot place, is moving up and down.

If it doesn't move smoothly the carb will not fill up with gas or will run low as your driving down the road. Make sure you check the battery As Well, if they become down the ignition system won't have enough power to keep the motorcycle running swimmingly. If you still haven't found anything make sure you valve lash has been checked at the correct mileage intervals. If not this can cause many problems with the way it runs.

Also you can screw a compression gauge into the spark plug holes and check that they are within 5% 10% of for each one other. If one is way down you have a serious problem either with the pistons, bore or valves. This should be a good start to finding a general trouble with your Kawasaki ZX7R.

FOR LATEST SERVICE MANUAL = ZX7R