BSA 1915 model K 557 cc chain-cum-belt side valve single frame # 9783 engine # 9878
BSA entered the motor cycle market with a sturdy 3 ½ HP belt driven single-geared machine, that was displayed at the 1910 Olympia show.
It was constructed almost entirely from BSA- made components and was produced from the company’s Redditch factory.
Within six months from their launching, BSA’s were selling well.
The machines were easily distinguishable among rival makes by their yellow and green painted tanks.
For 1915 there was a choice between the 85×88 3 ½ HP model and the 85×98 4 ¼ HP model.
This latter machine was offered as being especially suitable for sidecar work.
It also had the 3-speed BSA gearbox with foot controlled clutch that was introduced in 1914 and a double barrel BSA carburettor. Both models could be had in chain-cum-belt version or in all chain drive with encased chains, which made the machine 3 pounds and 5 shillings more expensive…