What does it mean to jump up and down on Honda cbr 1000 tachometer?

This is unstable idle speed, so it is necessary to check the engine carbon deposit and clean the oil circuit and throttle valve.

Engine tachometer is a direct feedback mechanism of engine speed, which automatically jumps. If the problem of the tachometer itself is eliminated, it means that the engine speed is unstable.

Possible reasons for unstable engine speed: The unstable engine speed may be caused by excessive carbon deposition in throttle, idle motor, air intake, intake valve, combustion chamber and fuel nozzle.