STAND 85 : Sunbeam Enthusiasts Discover Several Ingenious Features : Seven Distinct Types in a finely finished Range.
John Marston, Ltd. Sunbeamland, Wolverhampton.
“250 c.c. Sports” Model.—246 c.c. single-cyl. o.h.v. Sunbeam; dry-sump lubrication; magneto ignition; all-chain drive; oil-bath primary chain case; 4-speed gear, with foot control; fuel. 2¼ gals.; 26x3.25in. tyres.
Price with electric lighting (solo), £55.
A COMPREHENSIVE range of attractive models is to be found on the Sunbeam stand. This year there are seven distinct types, ranging from a 246 c.c. single-port o.h.v. model to the ever-popular 600 c.c. “Lion” side-valve long-stroke.
The 250 c.c. model is a beautifully finished job throughout, as, indeed, are all models in the range. In common with the other models it has many ingenious features, including the Sunbeam cam gear in which the cam pinion is built in two parts with the teeth held slightly out of phase by a spring, which compensates for any backlash. A simple form of decompressor is built into the actual cam. These improvements, coupled with the large silencer, have been found to make the Sunbeam exceptionally quiet, both mechanically and as regards the exhaust. Both the 250 c.c. and 350 c.c. models have a modified version of the new Sunbeam frame; it is of the semi-cradle type, but the rear chain stays do not extend any farther forward than the rear engine plates. “600 c.c. Lion” Model.—593 c.c. single-cyl. side-valve Sunbeam; dry-sump lubrication; magneto ignition; all-chain drive; oil-bath primary chain case; 4-speed gear, with hand control; fuel, 2½ gals.; 26x3.5in. tyres. Price with electric lighting (solo), £64 10s.
Two popular favourites are to be found in the 600 c.c. “Lion” side-valve long- stroke and the 600 c.c. o.h.v. Model 9. These two models have been little changed since last year. Both have the well-tried Sunbeam diamond-type frame, and the specification includes a constant- mesh gear box in which the drive is transferred to the off side. On both these machines it :s possible to fit the standard oil-bath rear chain case as in the past.
The specification includes an oil gauge mounted on top of the petrol tank. This 600 c.c. o.h.v. model, incidentally, is the only one in the range with a two-port engine.
In the case of the side-valve the valve gear is fully enclosed in an aluminium case, which is designed to allow a flow of air between it and the cylinder.
500 c.c. Model 9.—493 c.c. single-cyl. o.h.v. Sunbeam; dry-sump lubrication; magneto ignition; all-chain drive; oil-bath primary chain case; 4-speed gear with loot control; fuel, 3 gals.; 26x3.25in. tyres.
Price with electric lighting (solo), £71 10s.
While retaining many well-known Sunbeam characteristics, the new 493 c.c. o.h.v. Model 9 represents a big departure from previous Sunbeam practice. It has two “near relations” in the “Sports” 493 c.c. o.h.v. Model 9 and the 492 c.c. side-valve “Lion” long-stroke. All three models have an entirely new type of cradle frame. The engine fits snugly under a petrol tank with particularly graceful lines. A pivoting-type four-speed gear box, with foot control, is included in the specification.
In these three models, as in the 250 c.c. and 350 c.c. machines, both primary and rear chains are on the near side. The “Sports” Model 9 is, as its name suggests, a fast version of the standard Model 9, and the specification includes a high-level exhaust pipe, Dunlop saddle, and a narrow-section front tyre.