Hey all. I have a 1977 Columbia Commuter, it is in good shape and starts right up no problems. But it doesnt go anywhere it barerly pulls me or my brother who is alot lighter on level ground. I was wondering could there be a drivetrain problem or something? I mean we have it on the stand and it runs up nicely decent power, but once its on the ground it just doesnt go. Sorry if this isnt in the right forum but I think this can be considered as moped repair.