Cycling and Motoring Notes.

Horowhenua Chronicle, 10 December 1913, Page 4

Cycling and Motoring Notes.

Erom tlie Dunlop liubber Company of Australasia for the week ending Ist November, 1913.

Some very fine automobile racing lias been witnesed on .Brooklands Track, England, during the past season, and a fitting 1 climax lias been the display of speed by the racing 12-cylinder Sunbeam known as "Toddles V." At the final race meet of the season held last month this remarkable machine started 111 two handicaps from scratch and recorded a speed of miles per hour from a standing start in mile race, while in an event over 81 miles, UO.i miles an hour was recorded, also from a standing start. Needless to say the last-named figures are the world's best. During one lap in the latter event Hie speed was 118 A miles an hour, and it is safe to predict that this machine, which easily holds the one hour record of 107 miles 1072 yards, can easily wipe off the slate all the shorter distance world's rccords.

Several precautions have recently taken place over motor cyclists using machines with open exhausts, or with noisy ones. Many motor cyclists when remonstrated with over the noise their machines make declare That the muffling of the exhaust diminishes th epower of their machines very considerably. There is a misapprehnsion in the majority of cases, and it is doubtful whether there is any serious falling-off in power owing to further muffling of the exhaust, especially . when the silencer is sientificaTTy in<«ae. Experiments carried out in England some time back with cars proved 'that the loss with the better types of silencers varied from 1A to ; io per cent, the average being a 2 per cent loss of powernot much to pay for the silence. Similar trials with motor cycles demonstrated that loss in power was practically nil, thus upsetting the stock argument that an efficient silencer spelt back pressure. It having been proved that a motor cycle can be silent; and yet efficient, there is no excuse for a noisy exhaust, and there is no reason why a motor cycle should nol be almost as quiet as an up-to-date car.

Details of the wonderful 12 hours record established last month by a O-cylinder Sunbeam are to hand. The full distance was 1078 miles 400 yards some lti-1 miles better that the previous record - and it is interesting io note that the new 12 hours ligures are ahead of the previous 14 hours record. All records from 200 miles and upwards were secured, the now figures being 200 miles in 2hrs smins (j.2sec; 300 miles in Mrs Tmins 45.4secs; 400 miles in 4 hrs 12mins 15secs; 500 miles in shrs Idmins lOsecs: 000 miles in Ohrs 22mins 54.1 sees; 700 in ilea, in 7hrs % 29mins 20.5 see ; 800 miles in Bhrs ; >4inins 20.1 sees; 000 miles in Dln-s 53nuns 22.25 ec: and 1000 miles in 11 hrs Omins ■')B.Bsecs. The average speed for tiie one round of the (dock was nearly 90 miles per hour. Three crack drivers in Iv. Lee Guineas, D. Resta, and J. Chassaigne, took turn about at the wheel. The bore and stroke of the machine used was 80 millimetres by 149.0 millimetres, the R.A.I, rating being 23.8-li.p. Dunlop tyres were used iii this remarkable feat. One

tiling- is very certain if juotor ,speed continues to increase during I 1.914, as it has (luring' the present year, Brooklands track will soon be out of date, and unable to accommodato the pace attainable by the flyers.

It is very strange why I lie long stroke engine has not obtained mort favour in the world of motor cycles. In. the case of cars (lie short stroke engine, or at least the ''square'' engine has to all intents and purposes disappeared, it cannot be argued that the sole reason for this in the case of cars is that cars are rated for taxation purposes on the bore, the stroke not being considered. Undoubtedly this absurd system of taxation has had a very considerable say in the matter, but at the same time it is by 110 means the only reason for the predominance of the long stroke engine in the car world. This is proved by the fact; that the great majority of specially built racing cars are tilted | with engines in which the stroke i is considerably greater than the •bore, sometimes more than twice as great. There must, therefore be a reason fo rthis state of affairs Some time ago there was a controversy in England concerning the respective merits of the two types of engines. Mr Pomeroy, the designer of the Vauxhall car took up the cudgels for the 90 x 1 K) m.m. engine, while Mr Coata'en of Suubea mcar fame, entered the ring to uphold the merits oi: the 80 x 150 m.m. engine. Mr Coatalen stated in one sentence the greatest point ill favour of I he long stroke engine when he said that he would soouer "save_ an ounce in the weight of the piston • that a cwt. in any other part of I lie car. The remarkable performances of Sunbeam . ears this year proved, at all events as far as

cars are concerned, that Mr Coataleii's reasoning is correct. Tht; arguments in this controversy were chiey intcde dto show which type of engine was the best for racing purposes. It will then be ver yevident that the long stroke engine piston can be made considerably lighter than that of the short stroke. Take tho case of a 000 c.c. single cylinder motor cycle engine, this being the most popular type at present. As is well-known the dimensions that are generally used at present in order to give approximately this capacity are 85 x 88 m.m. bore anr stroke, respectively. In other words, this is what is commonly known as a "square" engine. Suppose now that the same cylinder capacity is adhered to, but change the dimension so that the stroke is approximately twice the bore-: one woul dthen have an engine with a bore of 08 and a stroke of KS7J m.m. these dimensions giving capacity of 499.Me.e.. whilst the dimensions of the "square" engine above mentioned give a capacity of -HJi.GI c.c.