21-03-2020, 03:28 PM
As Jamie says the arm drives the oddometer and does not affect the speedometer function so if you aren't bothered about measuring distance traveled you can use it with the arm disconnected.
What I think happens is that over the years dirt, corrosion or possibly dried up lubricant between the oddometer number wheels makes the mechanism stiff and causes the problem. I took mine apart, cleaned all the bits and re-assembled with a light oil which cured the problem.
Tony Press mentioned a local instrument maker who could repair it which is probably the easy option.
What I think happens is that over the years dirt, corrosion or possibly dried up lubricant between the oddometer number wheels makes the mechanism stiff and causes the problem. I took mine apart, cleaned all the bits and re-assembled with a light oil which cured the problem.
Tony Press mentioned a local instrument maker who could repair it which is probably the easy option.