Singer OHV Watercooled 4 Valve Racer, 1912
The new Singer racer with four overhead valves and water-cooled head.
Design of water-cooled head and valve actuating mechanism.
Singer 1912 4 Valve Watercooled Engine
The Singer Co. have evolved a very novel engine for racing purposes with which they expect to do great things at Brooklands. The power unit was designed by Mr. Louis Coatalen,. of the Sunbeam Co. The bore and stroke remain 85 x 88 mm. respectively, so that the machine is eligible to compete in the 500 c.c. class. The head is water- cooled, and in it are placed four large valves, two being for the exhaust gases and two for the inlet.
The ports are cast in the head. A roller chain-driven camshaft in front of the engine operates stout push rods, opening the valves by a neat overhead rocker system, which can be clearly
seen in the accompanying illustrations. The exhaust valves can be depressed by the usual hand lever through a neat cam gear bolted on to the lower top tube. Two small water radiators are carried pannier fashion, attached to the down tube, circulation being carried out on the thermo-syphon system. The magneto (an enclosed Bosch) is driven by a separate exposed chain off the end of the camshaft. The water-cooled head is bolted down to an air-cooled cylinder with tapering flanges.
Other Departures from Standard.
Besides the engine there are several unusual points on the machine, noticeably the webbed lug to take the rear ends of the top tubes, also the neat method of controlling the oil pump by a pedal mounted on the foot-rest. All that is necessary to inject a charge of oil is to depress by the heel a pedal fitted on the right footrest. This raises the pump handle by means of a Bowden wire, the plunger being afterwards depressed by means of an, internal spring. It is quite reliable, having received a prolonged testing at Brooklands.
The tank comes to the level of the top of the frame on one side, so as to give a greater capacity. The silencer also is unusual, but as its construction will be clear from the photograph a description is unnecessary. It is hoped that the machine will accomplish the speed of eighty to ninety miles per hour, and its performances will be watched with interest by followers of the racing game.
Caption: The complete machine, in connection with which speeds of 80 m.p.h are talked of.
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