CYCLING AND MOTORING.

Taranaki Daily News, 7 April 1916, Page 7

CYCLING AND MOTORING.

ECONOMY IN PETROL. A correspondent of the English jourpal, the Motor, lias contributed an interesting article on his experience in cutting down petrol consumption in the now general search for means of economising. The method adopted was as follows:—Four bottles were each filled with one pint of spirit, carefully measured. The ear, a 10-h.p., 76mm. bore by 89mm. stroke, was emptied of petrol by the simple expedient of running the engine until it stopped for the want of fuel. The reading of the inileometer was then taken, and one of the pint bottles of petrol was poured into the tank. The engine was started, and only stopped when all t'hc fuel was used up, and the mileage recorded was tliea noted down.

If one studies the results, one cannot fail to. see that a method of economy is available to every motorist—viz., by driving relatively slowly. One must experience it really to appreciate it, and good advice would be that each carowner should adopt the method indicated here, and thus have ocu]ar .proof till at he can much reduce his petrol consumption when he so wishes.. One has often heard that petrol consumption is increased by speed, but, to realise the fact, one should go through the experiment 'personally. ■ . The original jet was marked 95, 'but the makers of the carburetter stated that after two years' use it had increased to 105. They provided two jets to experiment with, "viz., 90 and 85. Old jet, 95.—When new/ this did 22Va to the gallon, but in August, over 1000 miles, it averaged 18. 90 Jet,—At 20 miles per hour, flat roads, one pint was consumed in 3 9-10 miles, or 31 2-10 miles per gallon. 85 Jet.—At 20 miles per hour, flat roads, one pint was consumed in 4% wiles, or 36 miles per gallon; 85 Jet. —At 30 miles per hour, undulating roads, one pint was consumed in 3% miles, or 28 miles to the gallon. 85 Jet.—At 20 miles per hour, climbing a steep hill on second gear, one pint was consumed in 2 9-10 miles, or 23 miles per gallon.

On the 85 jet this car was tested for speed and hill-climbing, and in each case was equal to the original jet, the only difference detected being that it did not pick up so quickly. Instead of an average of 18 miles to the gallon, the writer hopes, as a result •of these experiments, to get, say 25. This will mean that the increased tax js more than covered by the reduction of petrol consumed, which appears largely to follow the reduction of car speed; the ■reduction of the size of jet also helps, but it is obvious that, without changing the jet size, much economy can be effected.

Another writer in the same journal helps to attack the'fallacy of straining for economy by cutting down the fuel too much, and adds "a warning against .what some drivers have made into a veritable fetish—driving ou as much air and as little petrol as possible." Exhaust valves submitted to a weak mixture for any length of time will develop burnt and pitted seatings. And that sort of trouble is , far more expensive than ..aving a little petrol;

THE MELBOURNE-SYDNEY RECORD. Some further interesting particulars are available in connection with Mr." Boyd Edkins' recent drive ffom Melbourne to Sydney (385 miles) in lfi hours 55 minutes, some 15 minutes' faster time than the express train takes to link up the two capitals. The actual driving time was about 15 hours 55min., some 62 minutes being spent in stops for replenishments, etc.,. along the overland route. The petrol consumption averaged 17 miles to the gallon. Near Liverpool (20 miles from Sydney) one of the rear wheels struck a brick, in the dark, and split' the rim, necessitating changing the wheel. Some of the fastest travelling over intermediate sections were: Albury to Germanton, 37 miles in 50 minutes; Germanton to Gundagai (bad), 81 miles at 33 m.p.h.; Gundagai to Yass, 63% miles, at 43 m.p.h.; Yass to Gunning, 2G miles, at 46 m.p.h.; Gunning to Goulbum, 30 miles, at 44 m.ph.; Goulburn to Sydney, 120 1 miles, in the dark, J honrs 40 minutes. The big-host speed the indicator registered during the trip was "70" an hour along some good roads betyeen Gundagai and Goulburn. EVOLUTION OF THE PNEUMATIC TYRE. Motorists and cyclists of the present generation know little of the troubles and trials of tlic users of the early pneumatic tyre. What Mr. Dunlop gave to the world at the close of the 'eighties and what motorists and cyclists use today arc very different propositions, although the principle is the same: The motor tyre, as constructed to*-day, has nc- semblance to the first type of pneumatic, save that it contains compressed air. Tn IS9O, when the first Dunlop tyres, fitted on bicycles, reached Australia, they were as large as now seen on lightweight motor-cycles, with a wonderfully thick rubber tread compared with what now is found adequate, for there 'have been great advances in the manufacture and treatment of rubber since. The first type of tyre to reach Australia was made up of, an envelope containing the air tube, which, placed on the rim, was secured to it by a layer of canvas bring-brought over the envelope and the ends or cemented to the rim by solution, the canvas being cut at intervals to fit the spokes. Then came the rubber tread or outer cover. This, in the first tyres, was «ot an endless band, but was bevelled at the ends and solutioned together after the cover had likewise been secured to the tyre proper. This joint, howcvei carefully ■ effected, was a source of great trouble and expense to those who used them; the solution at the joint wore away, and gradually an opening was formed permitting the ingress of moisture and dust to the canvas beneath, which, ultimately weakened and the tyres blew out. Later the outer cover was manufactured in one endless piece, a great boon to the The sides of the outer cover (rubber) were also brought over the viiji and secured by solution, and when all was set a finishing ,4.rip of canvas slit at intervals to pass between the spokes was then cemented in the ordinary way by solution, a liberal supply of which was invariably carried by the cyclists. Tn appearance the tyre was not so clumsy as might now be thought, but its large size after the then,prevailing narrow solid rubber tyres on the. cycle wheels. made them appear unwieldy and heavy, and were variously called, by the smal\ boy and sometimes, by ,the small (minded) man, "road-roll-ers," "Gern'j " sausages,"* "balloons," and terms n' r ungainly meaning. Now when r " ' occurred all the ingenuity of ' l|P ':vdi«t s wa# called into play. He i.a> tbe puncture, and . having locates >t 1 ,v oiild pull apart the canvns.lt>.'' " " 'im, and then ,I ■: J" •••♦*»•

cover from the canvas. To reach the tube the canvas'beneath was cut across, the tube taken out, repaired, replaced, ami tlio cut in tile canvas carefully sewn up, after which the rubber cover and strip were secured by solution as before. Supposing, now, the puncture could not easily be located, the cut in the canvas covering under the rubber cover was niacin at the valve, the tube pulled out, the joint of the tube undone with the aid of benzine, and tying a length of cord to one end of the tube it was pulled out, so as to be tested under water, and when repaired, was drawn back into the tyre by the string and the tyre, closed up as explained. Punctures in those days cost 7s (id sometimes to repair. The first, type of valves used were 11011-release; if too much air was pumped in. well, the tyre sometimes purposely punctured to relieve it, for the pneumatic had to be very closely watched in. those days.