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British Motorcycles

Barr & Stroud Sleeve Valve Engine 1921

Barr-Stroud-1921-350cc-Sleeve-Valve-04.jpg
The single sleeve valve of the B. and S. engine, to which a reciprocating and oscillating motion is imparted by means of a pin engaging with a Skefko ball race set eccentrically in the half-time pinion.

Credit: The MotorCycle