CYCLE AND MOTOR NOTES.

Stratford Evening Post, Volume XXXIV, Issue 48, 21 October 1912, Page 7

CYCLE AND MOTOR NOTES.

Many new cars will lie taken on the roads this season, and many people now to motoring will bo driving them. Now, the automobile of to-day is a machine of a very advanced type; its many component parts have reached a degree, of fineness and accuracy of construction and accuracy of reciprocal movement comparable to the mechanism of a watch, for which of course there is absolute necessity. Very many of the parts are closely fitted, some moving at high, hut at varying speeds in relation to each other, while not ■a few are subjected to high temperature, in addition to the friction produced lay their sliding contact with each other. It is advisable' that those taking up motoring should be conversant with such facts. The use of material which will give a long life to the wearing parts is imperative. The cylinders and pistons are made of hard,

I close-grained, cast-iron, and, while maI chined as smoothly as possible with the best grinding plants obtainable, their surfaces, if examined with the «ud of a powerful magnifying glass, should present a surface apparently as rough as sand paper, and therefore efficient lubrication is an essential. Now all these facts are potent reasons why the owner of a new car should drive it easily and at moderate speeds, when first using it, gradually increasing both the work and the pace, and at the same time supplying adequate lubrication for all working parts. In this way wall the hearing surfaces gradually become “bedded” and result in the machine as a whole working harmoniously. Both locomotive and marine engines, on their trial trips are most carefully watched, and liberally lubricated before any speed is attempted, and it is logical that the automobile should be treated in the same way. The “explosions” that take place in the cylinders of a petrol-driven car are not, as the meaning of the word conveys, productions of a loud and sudden noise, but an extremely quiet function ; in fact, they make no noise at all, for there is noting upon which the expanding gas can react in such a way as to produce sound. After leaving the cylinder ,however, the gas at high pressure impinges upon the air, if the oxhaust is open, and by its impact upon the atmosphere, makes the racket that has upset the equanimity of many peace and quiet-loving individuals, and has been deemed the direct cause of legislation against muffler or silencer cut-outs. It is noticeable in a motor with a very efficient silencer that the air can ho heard passing through the carburetter, the timing gears may be audible, and" other parts of the mechanism may produce their slight characteristic sounds; hut little or no noise is hoard from the combustion chamber in which the socalled explosions are taking place in rapid succession. It is not the cause of whatever noise is heard in the silencer that turns the crank shaft; that was done by the noiseless expansion of gas in the cylinders forcing out the pistons. The great majority of motorists dislike changing from the top speed or gear to a lower; they endeavour to surmount all hills they meet without recourse to the change-speed lever—that is, if they think there is any possibility of the engine accomplishing the task. Still, it has been the aim of motor manufacturers to build cars with engines so flexible as to make a change of gear unnecessary unless for exceptionally hard pulling. While flexibility in a motor engine is an excellent attribute ft is, in fact, anything but economical to run a motor at all times under ignition and throttle control, using the same gear regardless of gradients andlroad surface conditions, ' because every motor is cap--;ible/ of' its most 'economical operation at-m Pertain speed, and the fnrthcrthjs. <speddMxSG departed 1 j r Om the greater the)waste of fiUcLlMoreover,.,rontinlions direct drive work necessitates relatively a larger engine. Obviously an engine-sufficiently powerful to propel a car up a fairly stoop hill on the direct drive must be run at a very small fraction of its capacity on a level road, ( undo f r? co/iditiotte- 'that ‘usually obtain in driving a tollring'car. It ia undeniable'That the modern petrol motor is a remarkably 1 efficient ‘ machine, but it is unreasonable-to ; expect it to maintain, i; when throttled 1 down to qnc-sev-enth of its capacity, the efficiency of which it is capable at normal outputs. The most economical motor for a car, clearly, is one that can be operated at an economical rate, while the vehicle is running under the conditions that obtain during the greater part of the time; and of necessity such a motor engine must drive through gearing when heavy pulling is to he done. The gear is embodied in the design of a car to relieve the engine on rough or steep roads, and a freer use of the change speed lever is advisable.