A little bit of history from Sydney would put you in the picture. Some
steam tram operations had the motors and trailers fitted with coarse
railway wheels so that they could run on railway track. During the
electric tram era some steam tram motors were retained with coarse wheels
so that they could transfer electric cars between isolated tramways and the
main system for maintenance. The electric cars were towed at quiet periods
on the suburban lines at very reduced speeds - 4 mph was the maximum
allowed on curves and through pointwork. This form of working was phased
out during the early thirties when a special road trailer was constructed
for such transfers - it was known as 'The Lizard'
David Bennetts
Canberra