Is The Speedometer Cable
Ferrule must bottom out with the speedo frame collar. Sometime new replacement speedo cables are manufactured too long.
If the inner speedo cable is too long, it will not allow the ferrule to bottom out with the speedo frame collar as in the first picture. If this problem is on taken care of, speedo failure will happen again….
Tip of cable can be ground down to allow ferrule to bottom out. Speedo cable may have to be replaced.