1929 Ariel 557cc Model A
The Ariel Model A is powered by a side-valve, 557cc engine with a three-speed Sturmey-Archer gearbox. It has dry sump lubrication with positive pressure to the big-end bearing, and other improvements for 1929 included enclosed sidevalves, with better forks and brakes. Electric lights and speedometer were optional.
Courtesy New Zealand Classic Motorcycles