Page 11 Advertisements Column 1

Sun (Auckland), Volume I, Issue 185, 26 October 1927, Page 11

A MODEL £45‘0 , 0 ADVANCE SPECIFICATIONS OF THIS NEW MODEL. The newcomer is a two-stroke _of 174 c.c., the bore and stroke being 60mm. x 61.5 mm. The engine is of the normal 3-port two-stroke type, but is unusual in that it is combined with the simplest possible form of twospeed gear box, and a minimum of power is wasted in the drive. An aluminium alloy two-ring piston is attached to the H-section connecting rod by a hollow gudgeon pin; the big end bearing is of the roller type. The crankshaft itself has an over-hung big end, and two ball-bearings on the mainshaft widely spaced apart, with a pair of gear wheels keyed to the shaft in the intervening space. There is a spring-controlled compression - retaining washer on the inner race, and a second steel washer on the outer race to prevent leakage, the pressure on both being applied in the same direction. Outside the outer race is a kick-starter pinion and a small outside fly-wheel. The two gears already mentioned are in constant mesh with a second pair of gears ou the lay-shaft, which also has ball races ou either bide of the gears. Both lay-shaft gears are free of the lay-shaft unless locked to it by a single dog clutch. The high gear wheel runs on a long sleeve made integral with the gear and has dog teeth on its inner end. Tinlow gear wheel is free to revolve on the outside of this sleeve, a bronze bush being interposed; there are also dog teeth on the inner end of the low gear wheel. Keyed to the lay-shaft is a sliding dog clutch, overhanging the dogs on the high get r wheel and lying between these and the low gear wheel in such a manner that an endwise motion will lock either of the two wheels to the lay-shaft. A multi-plate fabric clutch is mounted on an extension of the layshaft, and though it is located between the gears and the final chain drive, instead of in the primary drive, there appears to be but little disadvantage in this arrangement, as the moving parts are so small and light. A pinion on the magneto spindle engages directly with the low gear drive, so that, with the exception of the big and small end bearings, there are but four ball races in the engine and gear box combined, and but five gear wheels and two sprockets for the primary and secondary drives, the gear box and the magneto drive. Thus a very large reduction iu parts is effected, with an increase in simplicity and efficiency. With this arrangement the engine runs backwards, but this has no bearing on its performance, aud would be unnoticeable if it were not for the outside flywheel. Lubrication of the engine is by the petroil system, through an Amax two-lever carburetter, and the gear box has a tilling plug at such a level that it cannot be overfilled. An external kick - starter, with folding pedal meshes with a free wheel pinion on the crankshaft, a~sd the complete engine and gear unit is very neat and simple. Not less unusual is the frame, which is quite unlike normal motorcycle construction, though it appear? to be rigid, simple, and eminently satisfactory. The head lug is formed with two ears projecting backwards, and from either side of the head run twin tubes extending in an almost straight line to a point just in front of the rear spindle. From the head lug, also, twin tubes extend downwards to the front of the crank case; they are bolted at two points to the head lug, and at two points to the crank case. A third pair of tubes join the bases of the two pairs already mentioned, and are extended rearwards to form the fork ends. There is a saddle tube in the normal position, lying between the sides of the duplex frame and bolted to it by distance pieces, and at the bottom end by a .short engine plate, the lower part of which forms a bearing for the brake gear. The frame tubes are trapped and reinforced on all junction points, and the result is a light but rigid construction, which appears to be well up to the work for which it is designed. Over the top tubes fits a saddle tank, finished, of course, in the wellknown B.S.A. cream and green colours. The forward end of this tank is bolted by ears to head lugs, and the rear end is clipped to the top tubes from underneath. A single brake drum on the rear wheel contains two shoes, one hanuoperated and the other controlled b> a heel pedal placed on the left-hand side. The forks are of the link type, but built up in a similar manner to the frame; they are controlled by a single central barrel spring. Tyres of 25in. x 2.75 in. are fitted for colonial conditions. Lubrication for the frame parts is by means of grease gun throughout. A special Lucas lighting and ignition apparatus has been produced for this machine. The lamp is lit direct from the instrument without accumulators, but a stand-by dry battery is provided, and takes the form of a long tube containing a large-size electric cylindrical flashlamp battery. The large filler cap to the tank is so constructed as to form a measure for the mixture of oil with petrol. At the price of £45 (which does not include speedometer or electric light), this interesting machine should have a great future, especially as its performance is of a high order. A few laps of the B.S.A. test track showed it to be capable of well over 42 m.p.h., and of ascending the 1 in 4 test hill with ease from a standing start at the bottom of the hill. Special precautions have been taken to reduce the exhaust noise, the - * large silencer in front of the crank case being divided by a baffle, while both exhaust intake and tail pipe are formed in a special manner to reduce noise. The silencer is certainly reasonably efficient, and the machine handles with great ease. SAVE £3-10 BY ORDERING IN ADVANCE Bv ordering in advance a saving of £3/10/- cash can be effected. Full particulars of our special advance order conditions, together with details of EASY TERMS PAYMENT, will be sent on request. “USE THIS COUPON.’ SKEATES 3c WHITE. LTD. 48 Tort Street, Auckland. Please send mi* full particulars about conditions and details of easy terms plan m new Model A. 28 B.S.A. Motor-cycle. your advance order connection with the Na r GckATJ-S^WHITELTD • BICYCLE AND MOTOR IMPORTERS • 48 FORT STREET AUCKLAND. THE SUN Classified Advts. Bring Buyer and Seller Together