THE MOTOR WORLD.

Otago Daily Times, Issue 21639, 9 May 1932, Page 2

THE MOTOR WORLD.

FIXTURES . OTAGO MOTOR CLUB, (Motor Cycle Section.) May 17— Monthly meeting. May 21.—Acceleration test. June 4. —Trial. June 18,—Sporting trial. June 21. —Annual meeting. SOUTHLAND MOTOR CYCLE CLUB. June 3.—Reliability trial. HIT AND RUN. A Johannesburg taxi driver, found guilty of knocking down a man and then driving on, was ordered to be flogged. Tho driver, William Debriee, had caused the death of a cyclist. In passing sentence, Mr Justice Krause, of the Rand Criminal Court, declared;— “ I said some time ago that if motorists are brought before me for running away after killing a man by accident, I am going to give them lashes. I shall, therefore, give them to you, and I shall do the same in every case, whether the motorist is black, brown, or white.” A DANGEROUS HABIT. Quite a large number of Christchurch motorists have the habit of leaving the car in gear on hills as well as on the flat (says “Chassis” in the Sun). This habit of using the gearbox as a parking brake should always be avoided. If another car bumps a car left in gear the full force of the bump is transmitted to the gearbox, and costly damage can bo done in this way. Even in your home garage it is a bad habit to leave a car in gear. You may always remember, but other members of your family may not and may damage the car or injure themselves by unwittingly starting the car while it is in gear, BUILDING SILENT BODIES. The works of an English steel company have an interesting test for bodies, known as a shake test. Periodically a body is taken at random from the production lines; in its finished state, upholstered and fitted with non-splinterable glass, it is mounted on a chassis frame and conveyed to the shaker, a vicious instrument, capable of imparting 100 earthquake shocks per minute. Diagonal corners of the body are fixed solid, and the other diagonals are reciprocated to different amounts at different speeds. Thus, one corner will be lifted three inches 'very quickly and the other four inches more slowly. The body is tortured for 12 hours or more before it is released, inspected, and found unhurt. One body, indeed, was subjected to no fewer than a million shakes befoie it was fitted to a works chassis. Since then it has covered 30,000 miles—in silence. DRIVER’S THIGH. An affection which is stated to be fairly generally recognised by both medical and non-medical motor drivers and to which the convenient and descriptive name of “ driver’s thigh ” has been applied is discussed in the current issue of the Medical Journal of Australia. The complaint is described as a neuralgia or neuritis of the sciatic nerve, observed in those who spend a fairly large part of their time driving a motor car, and the symptoms vary from an ill-defined feeling of fatigue of the thigh muscles to those of a classical sciatica.

In directing attention to the affection, Dr John Hoets pointed out that the cause was a long-continued pressure on the sciatic nerve just before its division in the lower third of the thigh. This pressure was produced by the use of the accelerator pedal, which required the foot to be held in the one position, often for long periods. Treatment which he suggested was the adjustment of the seat. He explained that it would appear that the seat without the usual tilt was the best kind for the driver. The trouble, he. pointed out, occurred only when the driver sat in a bad position or the springs of the scat bad given way. THE SPEED LIMIT. When the motor speed limit wag removed in England last year, under the new Road Traffic Act, there was an outcry ftom a section of the English press—the contention being that the number of street accidents would be greatly increased when the long imposed speed ban was lifted. A recent statement in the British Parliament by the Home Secretary disclosed the fact that after 10 consecutive years, in which the number of street accidents has steadily increased, the first year’s operation of the new motor regulations had seen an extremely encouraging falling off in street fatalities. The_ official figures showed that nearly two lives had been saved every clay in street accidents during 1931—very striking evidence that after all the “driving to the common danger ” by-law is definitely better protection to the public than any arbitrary speed limit. TYRE DESIGN. Superficially a modern motor tyre looks very much the same as those that were produced 10 years ago, but the mileage results obtained to-day prove that there must be very great differences. What are they? In the first place, there has been no change in the fundamental principle of the pneumatic tyre as evolved by Dunlop in 1888, so that other reasons must be sought for the increased dependability, comfort, safety, and mileage of the pres-ent-day motor tyre. This better service is really the outcome of research and experiment, the whole business of tyre design and construction being now better undei-stood. This has led to improvements of various kinds, and, incidentally, to the reintroduction of early practices, notably the wired-on Dunlop type of attachment on the well-base rim and cord casing which were abandoned a-quarter of a century ago, but have since been proved to be better than the ideas that superseded them for a time.

It is indeed remarkable that Dunlop cycle tyres were being made in England and Australia with cord casing away back in 1895. Even in 1901 the Dunlop Company m Australia made motor tyres for its own De Dion Voiturette with cord casings. Yet the early development of motoring saw cotton cord discarded ior a cross-woven canvas. This was adopted and used universally until about 1920, when, with the evolution of the low-pres-sure tyro, the long-discarded cotton-cord fabric was brought back into general use for tyre construction. In pre-war days very little attention was given to tread pattern. Cross grooves in the tread and metal studs were sometimes used, but many tyres were made with plain treads. In later years much effort was directed on the evolution of a tough rubber non-skid tread, now recognised as a matter of considerable importance. Primarily its aim is safety, but it does more than that, because owing to providing better traction, road slip is eliminated, resulting in increased tyre life. Rubber alloys have been evolved, that will out-wear steel, resist cuts, and stand up to hard work over big mileages that were undreamt of a few years back. Some of the mileage figures reported from time to time to Ihc Dunlop Company by ear and truck owners, reaching as high as 9(>,000 miles with Australian-made tyres on motor trucks, driven under ideal conditions, are so astounding that they are well nigh incredible. But while these abnormal mileages are of interest, the important fact is that every owner of an automobile, who gives attention to propel inflation is obtaining treble the mileage that was attainable 10 years back, and only at about one-third of the initial outlay. Thus have tyre manufacturers helped to reduce the cost of automotive transportation and increase the serviceability of every type of motor vehicle. WEIGHT DISTRIBUTION. Sir Denistoun Burney, the man who designed th» British dirigible “R 100,” which flew from England to America and back, and who later astounded the automobile world with his ultra modern stream-lined rear-engined motor car, received a very fine and appreciative Bear-

By ACCELERATOR.

[ltems of news—short descriptions, of tours, the state of the roads, etc,, comment, oi inquiries will he welcomed by " Accelerator.’ J

ing from American automotive experts, on the occasion of his recent visit to the United States of America. His address to the Society of Automotive Engineers on “ Streamlining and Rear Engine, Mounting ” is stated to have created a deep impression on the American experts, for the fact was appreciated that Sir Denistoun knew what he was talking about. He scored a direct hit with the definite statement that the unscientific fundamental design of automobiles is costing the American people £100,000,000 annually in excess operating costs, owing to excess wind resistance.

Salient points stressed by this English expert were that the weight distribution of conventional cars is entirely incorrect for safe operation at high speed, while waste of power due to wind resistance assumes huge proportions. He cited tests conducted by Rolls-Royce in England which indicated that at 77i miles per hour, only 44 h.p. was required for a properly streamlined car, as contrasted with 78J h.p. for one of conventional build. An additional 22 h.p. would have been necessary if similar body room bad been required in the standard type body as in the streamlined one. Briefly streamlining reduces air resistance by half, while at 60 miles per hour the standard saloon car of to-day consumes no less than 75 per cent, of the power given off at that speed in overcoming air resistance. Another important point emphasised by Sir Denistoun is that overall weight distribution of a car governs springing, effects pitching during braking and acceleration. and largely governs the skidding propensities of vehicles while turning or braking; in fact, road holding and passenger comfort depend primarily on weight distribution. This is one of the major reasons why he advocated that the power unit should be fitted at rear of chassis. Other advantages are freedom from engine heat, fumes, and noises, and more room for passengers. It is worthy of note that many leading automotive engineers in U.S.A. endorse Burney’s ideas, but voice the opinion that the time is not yet ripe for such a radical change iu car design, as its unconventional appearance might not find ready acceptance by motorists. The Burney type of car will eventuate, but the change-over from present standard types will, it is predicted, be gradual. , STREAMLINING. It Is anticipated by scientists and mechanical engineering experts that not only will motor cars and motor coaches be streamlined in the not distant future, but also high-speed trains. Increased speed will not be the major objective, but rather decreased cost of operation. Applying the principles of scientific streamlining to automobile design, it has been proved that even at 40 m.p.h. air resistance ‘demands 60 per cent, of the total power. With correct streamlining —not just rounding off a few corners or a slight sloping, of the windscreen, for these halfway measures have little effect —a particularly large proportion of the power now required to propel a vehicle at even fast touring speed, can be saved, the percentage of saving increasing with the speed. If the body, wheels, and mudguards considered as a unit, are shaped according to modern aerodynamics, a car shape can be developed that will have but one-fifth of the air resistance of the present type of automobile, yet it will have the same ample passenger space as the modern sedan. It has been proved that a powerful sedan car, weighing about 32cwt, that requires a 90 h.p. engine for an 80 m.p.h. speed, lias 84 per cent, of its. power absorbed in overcoming air resistance, while if streamlined it could attain 100 m.p.h. with a 50 h.p. engine, instead of the 160 h.p. that would be required before the conventional sedan could reach such a speed. ■ A present-day car that has a top speed of 80 m.p.h. has a petrol consumption of about 10 m.p.g. Streamline the same vehicle and it will travel 30 miles to the gallon. It is for this reason that streamlining is sure to be generally adopted some day. As to trains, it is computed that a train that now travels at 40 m.p.h. could, if the engine and carriages were properly streamlined, attain a speed of 100 m.p.h. at an additional cost tor power of only a fraction of a halfpenny per mile. There is no doubt in the minds of experts whether streamlining will be adopted or not, the only question, they contend, is when it will happen and who will be the first to adopt scientific streaniautomobiles, the first radical move is likely to be sponsored in Europe, because such a change in design would not involve the colossal financial outlay that would have to be faced by the leading car manufacturers of U.S.A. in recasting their mass production plants to take care of a revolutionary type of automobile. For that reason the swing over to correctly streamlinel motor cars in America is more likely to be of a gradual nature. MOTOR CYCLE NOTES On account of the wet weather the sports afternoon was not held by the motor cycle section of the local club. During a lull in the showers a few keen members assembled at the club rooms and decided to view the timber cutting at Waitati. Unfortunately rain set in again and the remainder of the afternoon was spent in the club rooms. * * * On motor cycles without oil baths an important part of every overhaul is to ensure that heavy oil, grease, or, best ot all, graphite, is conveyed to every one of the inaccessible . bearings which are contained in a chain. THREE-CYLINDER ENGINES. In pre-war days there appeared a straight-three engine from the famous house of J.A.P. The engines were experimental, and not many of them were made. The design was considered to be ahead of the times. After the war a three-cylinder radial,. the Redrup, was made in small quantities and gave the impression of a very quiet, smooth-running little motor. The Guzzi is now turning out a three-cylinder motor in Italy. Possibly a few years will see more of this type, which certainly offers possibilities of a compromise between the four and tho twin. ECONOMICAL TRANSPORT. Taking the example of the average lightweight motor cycle, one of 250 c.c., petrol consumption would work out at over 100 miles per gallon, oil at about 250 miles per pint, and spares, tyres and repairs, according to mileage, reading conditions traversed, and driving methods. The annual license fee is 10s. compulsory insurance 15s, number-plates 2s 6d, and annual driving license ss. Assuming the mileage is 5000 per year, the items for expenditure would be: —Petrol, £5 11s; oil, £1; repairs and tyres, say, £3; license fees, 17s 6d; insurance, 15s. These amount to £ll 3s fid, which is approximately 4 S 3d per week, or ,53 pence per mile. If the annual mileage is greater than 5000, as it is quite likely to be, then the cost per mile will he still less. This form of transport is the most economical in the motor world, and besides being a quick and easy method of reaching work it provides for leisure outings to the quiet countryside which would be financially impossible without a motor cycle. There are now so many filling stations that it is easy to fuel all the people all the time. SPARKS The opinion is expressed that women are becoming better motor car drivers than men in France. * * * Financed by the British banker, Sir Eric Hanibro, the first British plant for the commercial production of petrol from coal is being constructed at Sheffield (England). ¥ ¥ V An observant friend informs me that of the cars travelling south between Dunedin and Milton on Tuesday afternoon 80 per cent, were driven by women.

The Duke of York has issued in England a strong appeal to all to promote good fellowship among all users of the highway, by exercising care and consideration for others.

The coroner at Hammersmith, commenting on the use of motor horns, said that motorists would be nothing less than a nuisance if they sounded their hooters every time they passed another vehicle.

No fewer than 447,857 driving licenses were issued, after the usual examination, in France during 1931. This is an increase of 10,122 over the number granted during 1930. Of last year’s licenses 43 per cent, were issued to women.

For cleaning celluloid side curtains use a mixture of equal parts of paraffin oil, methylated spirits, and water. This should be placed in a bottle, well shaken, and applied to the screens with tissue paper. After nibbing gently for a few minutes, clean off with a soft cloth or piece of silk.

In cold weather the starter motor may take a momentary current of, perhaps, 200 amps, to “unstick” and start a gummed-up motor. Prevent this heavy drain on your battery and starter by freeing up the engine with the starting handle before pressing the starter button on cold mornings.

The closing down of the Automobile Club of America, the oldest motor club in U.S.A., is announced from New York. The club was formed in 1899 to promote motor sporting events. In 1920 resident members of the club alone totalled 1600, but the last three years have seen a tremendous fall off in membership.