The Welbike was a British single-seat motorcycle devised during World War Two at Station IX — the "Inter Services Research Bureau" — based at Welwyn, UK, for use by Special Operations Executive (SOE). It has the distinction of being the smallest motorcycle ever used by the British Armed Forces, Between 1942 and 1943, 3,641 units (plus a prototype and some pilot models) were built and although it was not much used by the SOE, some were issued to the British 1st and 6th Airborne Divisions and some were used at Arnhem during Operation Market Garden. /From Wikipedia/
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