Smiths speedo service

When you say that the speedo drive is turning do you mean that it is turning at the rear wheel or do you mean that with the cable disconnected at the speedo head the cable is turning when the rear wheel is spun? Are you sure that the speedo drive cable inner is not broken?

Your speedo is a chronometric type, right?

David:

How about giving us a little history?

Was the speedo ever working?

Have you changed anything?

Here isa self diagnostic idea:

Remove the speedo from the headlight shell,

Make a tool from a nail, ground to the correct square dimensions to fit into theconnection of the speedo and cut off the head of the nail.

Put the round end of the tool into a variable speed drill and and insert the square end into the speedo. Check the end of the cable by rotating the rear wheel to see if the input into the speedo should be clockwise or anti-clockwise. (as I remember it should be anti-clockwise) Set the drill accordingly and run the drill speed up slowly.

Hopefully you will get some speed indication.

On a magnetic speedo the needle should sweep up and back smoothly. On a chronometric the needle will jerk up and down in increments.

If all is well I would suspect the drive at the rear wheel. You mentioned that the end of the speedo connection appears to be worn. That is possible of course but I have never seen one worn out to the point that the cable would not drive it. There is a possibility that the inner cable is too short to fit fully up into the speedo. I do not know what the "stick-up" should be, perhaps someone else here can say. To measure the stick-up first disconnect the cable at the rear wheel drive. Then push the inner as far into the rear end of the outer as it will go. Then measure the amount of the inner sticking out of the speedo end of the cable.

Hope this helps

Mike Sullivan

Branch Secretary

Northern California NOC

Up the rebels, Happy Fourth of July