SUNBEAM. (Stand 129.)
3½ h.p.; 85x88 mm. (499 c.c.); single-cylinder four-stroke; side-by-side valves; drip feed lubrication; Amac or B. and B. carburetter; chain-driven magneto; three-speed constant mesh type gear; enclosed chain drive; Dunlop or Bates ,650 x 65 mm. tyres. Price £155 8s.
John Marston, Ltd., Sunbeamland, Wolverhampton.
Although the capacity of the Sunbeam single-cylinder engine is only 499 c.c, it has proved capable of the severest sidecar work, and for dual purposes it stands in the highest rank. Famous long ago on Sunbeam pedal cycles, the oil bath gear case forms the most prominent feature, although the three-speed gear box is also a very fine piece of work. Of course, the rear wheel is instantly detachable without disturbing the drive or gear cases in any way. Laminated front springing was first adopted on this model, last year, and is retained both in standard and in T.T. version, the latter differing only in the substitution of dropped bars and foot-rests. This T.T. machine must not be confused with Messrs. John Marston's commendable attempt to provide a really fast and light solo mount, not dissimilar to the machine which won the 1920 Senior T.T. In this machine weight has been sliced off wholesale, leaving only those features which will delight the heart of the speedy soloist. Parallel link forks, a lighter gear box without kick starter, simpler braking on dummy belt rims, all contribute to the good cause of decreased weight; while a special aluminium piston should mean increased efficiency. The transmission system is unaltered, and the sporting Sunbeam is priced at £152 5s.
8 h.p. J.A.P.; 85.5x85 mm. (976 c.c.); V twin cylinder four-stroke; side-by-side valves; drip-feed lubrication; Amac or B. and B. carburetter; chain-driven magneto; three-speed constant-mesh type gear; enclosed chain drive; Dunlop 650x55 mm. tyres. Price with sidecar £237 6s.
For those who desire a great reserve of power for really heavy passenger work the well-known J.A.P. engined outfit is still a centre of attraction. Following very closely the general lines of the smaller touring machine, it holds an enviable position in its class, and for 1921 has not been altered. Large mudshields and the new Brooks cantilever saddle are fitted.