MOTORS & MOTORING

Dominion, Volume 10, Issue 2889, 29 September 1916, Page 9

MOTORS & MOTORING

[By Clutch.] Hare and There. Speculation as to what will happen after the war, in connection with the huge army of motor drivers, _ gives plenty of scope for the imaginative (.says an English writer). "There is one change," he states, "which it is very easy to forepast, namely, the lessened importance of the professional car driver. This will not ho brought about by the decreased number of cars for general and purely business purposes, but by the enormous increase m the number of persons who have become motorists during the war period. If I were beginning my career and. looking for a suitable employment, the last I should be inclined to up would be thiit of professional chauffeur. It i 8 not' 60 many years ago that the trained professional driver was a man whose susceptibilities had to bp carefully considered; he was generally rated a good many degrees higher than a mere coachman, and was inclined to placo himself in an entirely different category. One of the truths that the war has forced home is that no special intelligence is required to drive and look after a mod? ern car." The resurrection of the storage battery as a standard part of tho equipment of a motor-car, which has been brought about in United States by the introduction and popularity of the electric starting-lighting set, has led to a new development in that very go-ahead country. This is the establishment, by a. special company, of an organised system of battery interchange, just as compressed acetylene cylinders are exchanged. "A battery that never wears out!" is the attractive slogan of the concern, which, when its standardised batteries are purchased, has arranged for the interchange of full batteries for spent ones at a small and uniform charge all over the country, thus saving battery upkeep, expense, and loss of time in charging. A Victorian writer with a weakness ,for statistics, states that, tailing as a basis for calculation the motor imports for. the first six months of 1916, tlie taxes that motorists will pay during this year will amount to the enormous sum of £1,300,000 for tho Commonwealth. As the number who use motors in Australia does not exceed 40,000, these people are the heaviest taxed class. The above sum is made up by Customs duty on cars and tyres, and the taxes paid under the State Motor Oar Acts. The duty on petrol and oil •now amounts to large figures. If the number of cars imported is greater in tho latter half of the year, then the above estimate will be exceeded. Motor cycling in England is being hard hit by the limitation of petrol. In some instances only G gallons of fuel is being allowed by motor cyclists for three months. This means only two quarts of petrol a week. There is a great outcry in England owing to, tho extraordinary manner in which petrol allowances are being apportioned. Ligliting-up time: To-day, G. 2 p.m. Next Friday, 6.9 p.m. The Effect of Tiro Pressures on Steering. Tho factors that enter into the making of easy steering aro many and varied. Over several of them the driver has no control, as they are inherent to tho design. Over others, however, he may exercise considerable influence, and, assuming that proper attention has been employed' in matters of cleanliness and lubrication, no factor plays such an important part in securing oomfortablo and) effortless steering as the degree of inflation of tho front tires.

A very,simple experiment will prove the truth of this statement. Let the owner take his car out on the road and make a couple of trial runs, first with the front tires inflated to thirty pounds, and, secondly, to sixty pounds pressure. 'These pressures arc extreme, hut they 'help all tho better to emphasise the contrast. In the first instance, the tires will be "squashy,"• .a comparatively largo area will be in contact with tho ground, and will offer considerable resistance to any effort I made to deflect the oar from a straight course. . This will bo most noticeable in cornering, when the "drag" hecomes so great as to require a distinct muscular exertion. On the other i hand, with' the high pressure, there will bo noticed a distinct liveliness, the steering will answer to a touch', aud all traces of that clinging, sucking action will havo gone. This change is caused solely by the reduction in contact area, duo to tho higher pressure in the tires. Immediately, however, we begin to notice tho ill-effects of tho hard tires in increased vibration, which, in a long run on lumpy roads, beoomes ■unbearable. We are thus compelled' to decide upon a happy mean in pressure, taking iiito account tho two factors of easy steering end vibration, and the better sprung a car is the higher this pressure can bo with comfort. Looation of "Knocks." The oondition of running parts on a car can, to a considerable extent, bt* gauged by the sound produced. After .tome experience in the location of noises and "knocks," -and boing able to judge the cause from tho nature of tho noise or kno?k, it is possible to effect a considerable saving .of time, aud probably save a visit to tho repair shop. As aids to knock detection there are 6everal appliances on the market made on tho principle of a physician's stethoscope. A correspondent, writing to a trade paper, explains how he made a very efficient knock detector from an old telephone receiver. He removed the interior magnet with its coil, leaving only the thin iron diaphragm in position. The open end or lower part of tho receiver was fitted with a motal bush drilled centrally, and through this a long steel rod 5-i(3 inch diameter and pointed at each end was passed, interior pointed end was adjusted so as just to touch the 'diaphragm, the other pointed end being placed upon the part it was desired to test. AVith the ear applied to receiver the vibrations transmitted along the steel rod to the diaphragm could bo clearly detected and. oile sound distinguished from another, which would be impossible in the ordinary way. As these old teloplwne receivers cau be obtained cheaply from dealers iii; second-hand electrical and l scientific oddments an inexpensive and useful appliance can be made in the manner described.