Originally Posted by
clasher
You can see it in the pic, the white cable has the little gear on it.
This is a cool bike. I know there's a distributor in Canada (babac) that sells 571mm tires too but I would imagine they are the same CST tires you found. A friend has an old CCM that has the same tires and they were the only ones I could find in that size that are anything close to balloon tires.
That white cable is the disconnected front cable for the front drum but I think everyone is on the right track. I cleaned that ring and it has "Smiths Motor Accessories Limited" stamped into it. I think Smiths made car gauges so it would make perfect sense that it is some kind of odometer.
Also some pics of the bike as it currently is while I wait for the chromed bits