While I'm in a testing mood I decided to take the old DC trolleys out for a spin. A few weeks ago John kindly gave me an AHM United Transit trolley, which means I now have two, and two makes a fleet :-) You can see they both run quite well for 45 year olds after suitable cleaning and lubrication.
It turns out that orange and green AHM trolley has a burned out motor, and that green and yellow two-truck Bachmann trolley in the lower right corner that I bought as-is at a swap meet last fall runs terribly. The gears grind something aweful - I don't think they mesh properly - and seem to have trouble making the trolley move. Also, the trucks have very limited rotational movement and can't negotiate the tight Mortimer Park loop. However, I think if I ground out the openings in the chassis I might get some suitable rotation out of the trucks.