I remember those rolling on the front wheel. In fact an older friend had one, you pulled a lever to lift the motor off the wheel. I also remember it being very problematic if your front tire went flat!I recall was a BSA Cyclemaster too and a few other manufactures had similar ideas. I do recall one which sat on a carrier over the wheel and had a pulley rubbing on the tyre
Good looking bike!
Looks like a good size tank, maybe 1 1/2 gallons?Raleigh Runabout 1967
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