MOTORING

Hawera Star, Volume XLVI, 5 March 1927, Page 14

MOTORING

By " MAGNETO.’

SKILL IN REVERSING. VALUABLE KNOWLEDGE. SELDOM ACQUIRED, Motorists who are fortunate enough to live in wide streets where a spacious garage entrance is provided, are prone to neglect to attain a proficiency in reversing. The ability to reverse with precision is worth acquiring. It may save an awkward situation in a traffic jam, or it may be the means of averting a collision. Many drivers feel helpless when steering backwards, but after very little practice it is possible to drive in reverse at 10 m.p.h. without deviating more than a foot to either side. The art is better learnt with the assistance of an observer.

The best plan probably consists of choosing a slight down-grade, and, with the beginner at the wheel, allow the ear to coast slowly down backwards the instructor standing meantime on the offside running board, when he can conveniently rectify steering errors while having the hand brake (if right hand) within convenient reach. Hav ing learnt to pursue a not-too-erratie course the beginner will have attained an efficiency equal to that of most owner-drivers.

Recently two well-known drivers, whose names are to be seen in the lists of entries for nearly all the big English competitions, had a reversing race. The course chosen was a quiet, but broad road, and the length of the race was to be half a mile.

At the first attempt, both cars ran off the road within 200yds of the start, and it was not until the third attempt that' one of them reached the finish.

In such circumstances, assuming that the need for speding in reverse should ever exist, probably the most satisfactory tactics would be to set the hand throttle to a speed of about 15 m.p.h. and confine one's attention solely to steering, when going astern, needs all the centralisation that one can possibly give it. The reason for this is that motor-car steering gears are specially designed to be effective when proceeding in a forward direction and in seeking mechanism which is efficient when the car is going ahead designers must sacrifice, to a greater or lesser degree, the controllability of the steering when the ear is proceeding astern. GLANCE TO THE FRONT. Even the most expert drivers' will not risk backing out of an awkward position without at least casting a few wary glances at the front of the car, for, when, it is being reversed, the front wheels do not follow the track of the back wheels, and it is extremely difficult to gauge with any accuracy the exact course which they will take. When backing and turning at the same time, always remember that it is the front mudguard farthest from the centre of the imaginary circle; being described on which one’s attention must principally be fixed. It would be impossible to estimate how many thousands of front rvings are damaged during the year by drivers who do not bother to follow this rule. If one drives the front of the car into the gateway and then reverses on the other lock it will be found that several locks are necessary before the car is pointing in the reverse direction. If, on the other hand, it is driven past the gateway and backed in, it will be possible to drive away immediately on locking over the steering, unless the steering lock of the car in question is exceptionally meagre. Before the days of efficient engines and gear boxes, and rvhen cars were generally underpowered, it was inot unusual for drivers to have to reverse up a steep hill, the ratio provided by the reverse gear being considerably lower than that of the first gear. Today. these ratios are still widely separated, but, although it is not often that reverse has to be called upon to conquer a hill with a modern light car, it is well to bear in mind that, should such an occasion arise, a slow, certain climb can be made in reverse backwards.

However skilful a driver may be at reversing, it is most inadvisable, if a ear begins to run away backwards when climbing a hill, to endeavour to steer safely to the bottom. A much better plan is to direct it instantly into the side of the road. ,

ALIGNMENT OF WHEELS.

ACCURACY ESSENTIAL. Accurate alignment of the four wheels of a car is necessary to effective and safe operation. Mal-align-ment may have serious results in several directions. It makes for much increased tyre wear, and it adds very considerably to the risk of skidding, while if the loss of alignment is in respect, of the front wheel particularly, steering is effected, especially at speeds.

This trouble may be caused in a variety of ways. Often undue settling of one of the springs and not the other will cause the alignment to suffer. Another cause is the shifting of the axle along the spring. This is not a verv frequent cause, but in some cars it is known to occur. In modern cars everything is done to maintain alignment without the necessity for adjustment by the owner. In some cases the makers erect the chassis so that the two front wheels faee in to each other slightly when the car is quite new. The first wear, which takes place in the articulation of the steering, has the effect of correcting this, and, when the bearing surfaces of connecting links has settled in, the wheels attain correct alignment.

Settling of the springs unequally may often be caused by driving the car with a single occupant, or the constant use of it unevenly loaded. Designers have canvassed various types of springing relative to this liability to assume inaccuracy of alignment, and it is a fault rarely seen except in old cars. But the driver who finds his control becomning eccentric -would do well to have the vehicle tracked up and any deficiency in this respect eliminated.

At Home and Abroad

BAD TYRES.

LOST LICENSES.

PETROL CONSUMPTION. POINTS FOR CONSERVATION. AVOIDANCE OF RESISTANCE It has boon conclusively proved by bench tests that the petrol-air mixture which results in the maximum of economy in the car engine is considerably weaker than that which is normally used to give good power and acceleration. Consequently it is open to any one to fit somewhat smaller jets if he or she desires economy at the expense of other automobile virtues. The essential points in connection with the carburetter are the importance of ensuring that no petrol is being wasted through persistent flooding—indicating a faulty needle valve or float —or through loose petrol-pipe connections, and the need for setting the slow-run-ning adjustment in such a way that the idling speed is low. Curious though it may seem, much more can often be done to reduce petrol consumption by attending to other parts of the chassis than by tuning r the carburettor. It is essential that everything should run as freely as possible because any part which is binding or dragging produces a resistance, the overcoming of which demands a continual and entirely wasteful power output from the engine over and above that which should be ordinarily required. Quite frequently, too thick an oil is used in the gearbox so that until the car has run for, perhaps IQ or 15 miles, this thick oil has a pronounced' braking effect upon the transmission system. Parts such as hub bearings should be kept well greased, and it is also important that the tyre pressures should be fully maintained, not simply in order to keep the covers in good condition, but also because a flabby tyre produces a greater resistance to rolling than one which is properly inflated. The brakes also require attention in order to ensure that there is no rubbing; even if the shoe clearances are correct it is quite .possible that one or the other of the brakes is not freeing itself properly when the pedal is released owing to lack of lubricant and consequent stiffness in the operating gear. This can best be checked by placing the hand upon each brake drum in turn after a short run in order to see whether any one of them is running hot. By these simple methods the rolling resistance as a whole can be reduced materially, and this has in itself quite a marked effect upon the rate at which petrol is consumed. On an ordinary macadam road in good condition the resistance to motion on the level at low speeds should not -be more than 601bs per ton, which means that the car should just roll slowly down a slope of about 1 in 4.0. A car can also be tested for free , running on the level by driving at a set speed'and declutching when a certain landmark is reached, then allowing the car. to coa.st until it comes to rest of itself. If the speed from which the test is made is' 15 m.p.h. the car should cover a distance of 120 yards before coming to rest if it is really running freelv.

SOURCE OF DANGER. Every new tyre to-day lias a nonskid design embossed upon it, and this is done not for the sake of ornament, but for the very important reason that the deeply-cut grooves and patterns are designed to prevent skidding. When these patterns are worn out, the tyre becomes less safe, and, if left untouched, is liable to become a danger. The average life to be expected from a tyre is .10.000 miles, after which the cover can be re-treaded if it is in good condition, other than worn tread. It is a penny-wise-and-pound-foolisli policy to keep tyres too long in use. Moreover, there is a mistaken idea that so long as the back tyres are good, anything will do for the front wheels. As a matter of fact, it is more important to have good tyres on the front wheels than on the back. A “blow out’-’ at the back is in itself not necessarily dangerous, but a burst on a front tyre is invariably a source of danger. Next to bad brakes,, bad tyres are possibly the greatest source of danger in motoring.

The best position for a worn tyre, to be run from an economical point of view, is the right-hand front wheel, where there is the least wear.

DUPLICATES OBTAINABLE. Owing to an ambiguity in the Motor Vehicles Act, local bodies have been concerned with the legal position 'in regard to the issue of duplicate drivers’ licenses to replace those lost. The Minister, of Internal Affairs has now stated that it is quite in order to issue a duplicate provided that the applicant makes a declaration regarding the loss, and that the police are advised of the loss. It is also pointed out. that the duplicate must contain any endorsement which was on the original. The Minister advises local bodies that they may charge the full fee of os for the duplicate. This has'been the practice of most bodies up to the present. It is obvious (states a contemporary) that the purpose is to make motorists cautious, since licenses would be treated with scant respect if they could be replaced for a mere shilling. It may be undesirable for a license to fall into the hands of some unqualified person, but it is very unlikely. People who have access to motor cars are usually very eager to qualify for a driver’s license. The number of people who would use another person’s license to defeat justice cannot be great. In any case the illegal holder cannot use the license for more than one year, and when he | exhibits it he runs the risk of having | it identified bv the number.