ARIEL ENGINE AND FRAME PREFIX NUMBERS 1926 TO 1930 This list has been compiled from details listed in ‘the Ariel Story’ by Peter Hartley and the Draganfly Motorcycles catalogue of Ariel parts. The model year for vintage models is understood to have begun some time between August and November of the previous year, so that, for example '1929' means November 1928 to October 1929. Post-vintage years, the model year is understood to follow the more commonly reference period for British manufactured bikes, which is nominally 1 September to 30 August, such that a 1939 model began in September 1938 and ran to August 1939. However, the actual release of models was always dependent on production timetables, which sometimes saw these periods slip by a month or two. The combinations of engine and frame prefix letters given are those of the majority. It was sometimes the case that late engine numbers of one model year were dispatched in early frames of the next model year and similarly e