Louis Clément built aircraft in Bordeaux, Lyon and Boulogne-Billancourt, and like many other aircraft manufacturers after the armistice, began constructing motorcycles. The first machine was a 540cc 55° V-twin presented in 1919. The engine was quite unusual, having a shared cylinder head, unconventional spark plug locations, and fully enclosed valves. Dry sump lubrication was employed with a backup hand pump, the fuel tank acting as an oil reservoir.
Both primary and secondary drive were by fully enclosed chains.
It was a very handsome motorcycle with many innovative solutions, but was too expensive for the majority. Production of the twin ended around 1921, and the single did not last much longer.
This machine, which is one of the most original motor cycles in the show, must not be confused with the well-known products of Clement Freres, who have unfortunately decided to retire from the motor cycle trade.
The whole of the Louis Clement motor cycle is extremely novel, and shows a careful study of the more advanced section of British thought combined with excellent design and ingenious construction.
A V type twin-cylinder engine having a bore and stroke of 62x90 mm. respectively is formed as a unit with a three-speed gear box of the sliding type. The
clutch and front chain are entirely enclosed in the crankcase casting, and the gear-driven magneto is mounted on the top of the gear box.
At first sight it would appear that the cylinders are joined by a common combustion space, but in reality the well-ribbed casting which connects the detachable cylinder heads forms a cover for the enclosed overhead valve gear and cam-shaft.
The camshaft lies across the frame and vertically above the crankshaft. It is driven from the crankshaft by a vertical shaft and suitable bevels, the overhead valves being operated there from by rockers.
The final drive from gear box to rear wheel is by means of a chain fitted with 3 a shock absorber, and all wheels, which are of the disc type, are interchangeable, and fitted with internal expanding brakes. At present the engine is lubricated by a sight-feed drip, but it is intended to adopt a mechanical oil pump.
The frame is constructed partly of tube and partly of steel pressings. Pressed steel forks, whose motion is controlled by a leaf spring, are fitted to the steering head, which is solid with the main frame pressing. On this pressing, which extends rearwards to form the rear mud-guard, saddle stay, and tool box, rests the tank and the saddle, the latter being mounted on three leaf springs. Aluminium footboards are extended to form a very complete undershield and a speedometer is neatly let into the tank.
The Motor Cycle, October 1919
Excellent as are the pressed steel frames of the Louis Clement and Janoir, the buyer may be inclined to ask if they possess any great advantage over their contemporaries having tubular frames. The Louis Clément is another pressed steel machine which made its debut at the last Paris Show, and which now appears in an improved form. In 1919, however (there was not a show in 1920), a twin-cylinder model was exhibited, and this has been abandoned in favour of a Train single-cylinder two-stroke of 500 c.c. capacity.
The Motor Cycle October 13th, 1921.