GPZ 550 Tach Issues

Having problems with my tach, it will not go below 4000 rpms but once I rev the engine over that mark it will working acorrdingly and I can't get it to switch between the tach and voltameter functions. Anything specificaly that I should look for, or just make sure I'm checking all the connections?

Thanks,
Nate

Alright I found that I can tap the face of the tach and it will return to the proper mark. Does this simply mean it is sticky, are there any remedies?

Thanks,
Nate

Isn't your year cable-operated? Maybe It's either not attached completely, or the cable is stretching. Check the back side of the tach to make sure.

the motor is for a cable unit but the dash isn't and apparantely somebody ran an elctric tach conversion.