The Welbike is a British single-seat folding motorcycle produced during World War II at the direction of Station IX — the "Inter Services Research Bureau" — based at Welwyn, UK, for use by Special Operations Executive (SOE).

[1] Between 1942 and 1943, 3,641 units (plus a prototype and some pilot models) were built and, although 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.

The original prototype was designed by SOE motor cycle enthusiast Harry Lester,[3] from an idea developed by Lt.

Colonel John Dolphin, the Commanding Officer of Station IX, the secret Inter-Services Military Research Establishment based in a mansion called The Frythe (latterly owned by the pharmaceutical company GSK) an hour's drive north of London near the village of Welwyn in Hertfordshire,[4] which had been taken over for the war effort.

[7] The aim was that a paratrooper could remove the Welbike from its special green container (which was marked in white lettering with the words Motor Cycle) and its easily identified coloured parachute, and be on the road within 11 seconds.

[8] The prototype survived extensive drop testing at the Special Operations School at Arisaig in Scotland where it was demonstrated to the commando forces.

The Villiers engine was found to be seriously underpowered when ridden by a fully equipped soldier, so it was retuned to improve the power output.

[1] The simple design of the Welbike meant that it was easy and quick to produce and from 1942 went into full production for issue to airborne forces.

The final batch of 1,340 was the Mark 2 Series 2 and had "saddle" fuel tanks with a splash shielding between them, and an improved filler cap replacing the original design which required the removal of the pressurisation pump which was found to be too time-consuming.

The difference in weight between a parachutist and a container meant that they often landed some distance apart, rather defeating the purpose, and some were captured by enemy forces or lost before they could even be used.

The low power and small wheels also meant that they struggled to cope adequately with the often rough battlefield roads so were often abandoned by troops who found it easier to continue on foot.

[1] Another problem for the Welbike was that, by the time it was in mass production, much larger gliders had been developed that could carry bigger and more powerful motorcycles such as the Royal Enfield WD/RE.

The single-speed two-stroke engine proved too slow, and despite the high post war demand for transport, lack of power and reliability problems meant it was discontinued in October 1954.