How to Troubleshoot Speedometer Issues in Motorcycles?

It sounds like you're experiencing some frustrating speedometer issues with your `2000 kaw W 650`. A common culprit for erratic speedometer readings is the speed sensor. Cleaning it can sometimes resolve the problem, so I recommend using a cleaner like WD-40 or a specialized cleaner to ensure it's free of dirt and debris. Additionally, if you have any auxiliary lights installed, try turning them off, including the headlight, to see if that makes a difference. Sometimes, electrical issues can cause the speedometer to behave erratically, so monitoring the voltage can be helpful. Ideally, the voltage should be between 13.6 and 14.1 volts. If you notice significant drops, it could indicate a failing stator. If the speed sensor cleaning doesn’t help, it’s worth checking the connections of the pickups. A loose connection can lead to issues, and if one of the pickups is damaged, it may need to be replaced. It’s also important to ensure that the wiring is intact, especially if one of the wires is supposed to be a ground. If you’ve checked everything and the problem persists, consider having the stator inspected. A burned-out stator can cause various electrical issues, including erratic speedometer readings. If it’s found to be damaged, replacing it should resolve the problem. Keep an eye on those connections and the condition of the sensors, and you should be able to get to the bottom of this issue.