This is a 4hp side valve unit manufactured by V. Antoine Fils of Liege, Belgium, which firm was a well-known supplier of engines as well as building complete machines. Antoine also supplied car and aero engines in the pioneer days. The engine features chain driven Bosch magneto ignition, a two lever carburetter and total loss lubrication from the hand pump mounted on the fuel tank. Transmission is by direct belt drive and the footbrake is a block operating against the inside of the belt rim. The brake pedal is mounted on the near-side as part of the footrest assembly. Tyres are 26 x 2.25in.