In the early 1920s, British and European truck manufacturers experimented with double drive tandem bogey 6x4 truck chassis. Some also developed halftrack systems to give trucks better grip on rough ground.
The British War Department encouraged the development of cross-country vehicles in light and medium configurations, including motorcycles. In 1926, the Royal Army Service Corps (RASC) replaced the rear wheel of a side-valve Triumph 494cc Model P motorcycle with a swivelling bogie with two smaller wheels. A rubber belt could be fitted over the two small rear wheels to improve performance over rough ground. This unorthodox three-wheeler machine was known as a ‘single-track 3x2 motorcycle’ or sometimes referred to as a ‘3x2-in-line motorcycle.’ They had turned a solo motorcycle into a halftrack.
When the RASC Triumph single-track 3x2 Model P underwent testing, it was found that when engine power was increased on soft surfaces, the whole bogie tended to tilt forward. This resulted in the leading rear wheel digging in and the back wheel losing traction. The same problem occurred when the bike was driven over the same course in halftrack mode.
In the hope of winning a War Department contract to supply the military with motorcycles suitable for cross-country as well as road work, commercial companies started to submit their own unorthodox three-wheeler machines for testing to the British Government’s Mechanical Warfare Experimental Establishment (MWEE).
In 1928,
