Speedometer rests on 100...

Usually this is a problem in the head, where the flywheel is rubbing on the cage, because of the play in the bearings that has developed over the years. But as Badsport says, the cage can be distorted by a mis-routed cable, with the same result.
The needle has no direct connection to the cable. The needle is driven by magnetism.
So would a new cable fix this?

*edit* Reread that. So is my speedo shot?