The 1922 Olympia Show.

SUN. (Stand 100.)

Rotary Valve Two-stroke.

2¾ H.P. Model.

• 67x70 mm. (247 c.c.); single cyl. two-stroke; rotary valve; drip feed lubrication: B. and B. carb.; chain-driven mag.; 3-3peed gear; clutch and kick-starter; chain drive; 26x2¼in. tyres. Price: Solo, £49 10s.

Sun Cycle and Fittings Co., Ltd., Aston Brook Street, Birmingham.

In the rapid advance that has been made in two-stroke engine construction, one of the most interesting innovations was the incorporation in the Sun-Vitesse engine of a rotary valve regulating the inlet port in the crank case. The details and working of this engine can be studied from a sectioned model shown on the stand.

The single-speed 147 c.c. Villiers-engined model is very attractive from the point of view of those who are seeking for real simplicity. Moreover, this machine is really light, as anyone can satisfy himself by lifting the example shown. It scales only 98 lb. when fitted with two-speed gear, whilst the single-speed model weighs but 86 lb. In addition to these models machines are also staged fitted with J.A.P. and Blackburne engines.

Features to be noted on the larger Sun-Vitesse models are the internal expanding brakes, transmission shock absorbers in the rear wheel, and their well-balanced lines generally.

Olympia Show 1922
The Motor Cycle, November 30th, 1922. Page 862