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In the Spalding Chainless the mechanism consists of a series of four bevel-gears used in conjunction with a tubular gear shaft. It is simple in construction and can be readily taken apart and reassembled whenever necessity requires.

SPALDING CHAINLESS.

The main driving gear, the largest of the series, is fastened to the centre of the crank axle, the power being transmitted from this by a smaller intermediate gear to the tubular shaft running through the right fork-tube, and this in turn transmits the power to the rear intermediate gear, which directly engages the gear secured to the rear wheel in place of the usual sprocket. The location of the main driving gear being in the centre of the crank axle, brings its position also in the centre of the crank-hanger barrel, and adds greatly to the appearance and symmetry of the machine; it also insures greater strength and divides the strain more equally on the bearings. The intermediate gears are securely locked to each end of the tubular gear shaft by a simple locking device, which makes it possible to remove and replace the gears conveniently and without the necessity of any special tools and appliances. The tubular gear shaft rotates on ball bearings specially constructed and designed to receive the thrust of the driving gear, and transmits the power to the rear hub. The lines of the rear portion of the frame present the same appearance as in bicycles of the ordinary chain type, the only perceptible difference being in the small aluminum cases which cover the gears. In this particular the Spalding Chainless differs from some others, presenting nothing unsightly to detract from the appearance of the machine.

DRIVING GEAR OF

SPALDING CHAINLESS.

The method of fastening the main driving gear to the crank shaft, and the front and rear intermediate gears to the tubular driving shaft, is original. The customary method of attaching these gears is to screw them on; but this method is impracticable, for the reason that the constant strain in hill climbing or in heavy work kept screwing the gears tighter and tighter on the shafts, thus making removal difficult. In the Spalding Chainless these gears are constructed with a tongue projecting from the back side of the gear. The gears fit snugly to their respective shafts, and this tongue is received in a recessed collar which is solid with the shaft, and which prevents any rotation of the gear on its axis. The gears are then securely locked in place by an ordinary lock-nut, which, when set up, makes a positive fastening that cannot work loose under any conditions, and one that can always be readily removed and adjusted.

The gears are cut by special machinery; they are theoretically correct, and are as absolutely perfect as it is possible to make bevel-gears. It is now nearly two years since Spalding & Bros. first undertook the matter of building chainless bicycles, and more than a year since their first complete bicycle was put into actual use upon the road. This same bicycle is in use today, and if anything, is better, after having been ridden over 25,000 miles, than it was originally. Its working parts show no perceptible wear, the frictional parts in the gears being polished more smoothly through use, and running better today than when the machine was first put on the road.

The Spalding Chainless has a 3-inch drop at the crank-hanger. The upper and lower main tubes are 1⅛-inch, the rear forks ⅞-inch, the rear stays are ¾-inch reinforced; wheel base is 44⅜-inch. The front fork has an arched crown; the fork sides are reinforced. The makers continue to use their well-known hub with straight tangent swaged spokes, 28 in the front and 32 in the rear. The cranks are 6¾-inch round spring steel, with a 72-gear.

The Spalding lady’s Chainless contains the same mechanical features found in the man’s model. The frame is the double loop drop, and has evidently been carefully studied. The cranks are 6½ inches of round spring steel and geared to 66½ inches. Some variations in gears are furnished.