Jumpy speedometer

My 1982 KZ1000 LTD with under 15 K original miles with electric speedometer drops to 0 when when you crack the throttle and registers the correct speed when you back off. Accelerate slowly and it registers correctly. This issue started in the last 3 residing seasons, the bike might be ridden 300 miles per season. Its garage kept and well cared for. Runs great otherwiseThoughts?

The Kawasaki service manual has a speedometer troubleshooting section & the 81-83 KZ1000/1100 pdf may be available here in the filebase. I don't know that much about the electronic speedos, but some of the stuff mentioned in the manual is to make sure the connections are good & the meter fasteners are tightened.


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Continuing with this jumpy speedo, I washed the bike, towel dried it and parked under a cover in my garage. Took the bike out for a spin 3 days later and now the speedo does nothing (very occasional jump).................but now the speedo will work and register properly and both low and high speed ....................but only when the front brake is activated. Let off the brake and its back to 0. Vexing to say the least.

Did you go thru & check stuff as per the troubleshooting flow chart in the manual? When you start investigating, the problem may present itself. One of the checks is to test for power to the speedometer. From the wiring diagram the brake light & speedo sensor get power via the brown wire circuit, as do the neutral light & oil warning light. I would start checking various points to see where power is or isn't. Troubleshooting electrical problems isn't my forte, but in addition to testing for power to the speedo, I would maybe remove the speedometer to check its wiring. Then check the wire harness, especially at the steering head. You should also check the ground wires, usually black-yellow.

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When is the last time the front wheel was off? Did it start at about the same time?

Thank you for your reply. The wheel was off the bike 2 seasons ago. The issue began before the wheel was off I am told Kawasaki used the electric speedos for only 2 years before going back to gear/cable setup

Thank you for this information. I will check out your suggestions. Appreciate your thoughts