PLEASE show the exact year and model of your bike. Kawasaki made MANY different KZ750 motorcycles in both 2 cylinder and 4 cylinder models. Obviously there are major differences between the various years and models, so showing the exact year and model of your bike will help others help you. If you put that information in your signature line it will always show up. Thanks, Ed
I am not sure about an extra relay, I have no idea what it would be for.
Eleven volts at the coil is too low. The battery should be close to 13 v, and there should be less than 0.5v loss at the coils. Either the battery is low or no good, or there are loose or corroded connectors between the battery and the coils.
As 650ed wrote, knowing exactly which year and model KZ750 you have will help folks provide good, specific help.
1982 KZ1000 LTD parts donor
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