In answer to Cyberjack, hubodometers used to be a common sight on the rear wheel of private bus fleets and many trucks and trailers as a low cost reliable method to track distance for maintenance purposes, be it mechanical or for tyres.
A lot of buses I used to catch had non functioning speedometers, so I presume they were fitted to over come that as well.
Nowadays they are still used a lot on truck trailers but not so much on vehicles themselves as they now employ sophisticated computerised dashes that have a reliable odometer in them.
Great memories setting them mounted on the old Leyland and Bedford buses and many trucks when Is little.
Glass you appreciated my collection. Of only I had some trucks and buses to mount them on!!
