These photos show the original throttle cable out of my signature 1955.1 3100. Note the punched-in dimple in the outer cable sheath, to add friction to the inner sliding wire. It worked fine until replaced last year due to broken/shortened inner wire at the carburetor. For the new replacement throttle cable assembly, a dimple was center-punched in the outer sheath similar to the factory original.
The new throttle cable works as before and holds its position when pulled out.