The [Crescent chainless] is of the bevel-gear class, having its rear pinion on the forward side of the wheel hub, the shaft passing through the right fork. Its most distinctive visible feature is the broad U which holds the wheel. This broad U or latch-piece has the wheel spindle carried in an open hole or slot in the bridge over it, so that the wheel can be withdrawn and replaced as readily and in the same manner as on the usual chain models; the appearance at this point will at once distinguish the Crescent from all others, at a glance. Another peculiarity is that the rear wheel is readily adjusted laterally on its spindle, so that the fit of the two gears is in easy control. By loosening the two nuts outside the wheel, the rear wheel slips out, and by loosening the nuts on the spindle itself its position is adjustable so as to make a proper fit of the two gears. The wheel can be removed and replaced without disturbing the bearing adjustment, and the hub gear goes on interchangeably with the usual sprocket, so that if the wheel itself should break down a chain wheel could be taken off another bicycle and substituted; the crank axle, bearing nuts, etc., are similarly interchangeable between the chainless and the chain models. The rear hub has twenty-four teeth; the shaft has twenty-three at the rear and fifteen at the front, where it meshes with forty on the crank axle gear. Ball retainers are used throughout, and the gears themselves form cones for the bearings. Felt washers are fitted, except that the bearings in front are protected by the washer directly behind the circular cover plate which is set into the enlarged end of the crank hanger. Several of the wheels have been subjected to severe tests under both ordinary and extraordinary road and weather conditions, and we learn have responded admirably in every instance. The price is $75.
THE CRAWFORD CHAINLESS.
The Crawford chainless is of the bevel type, and has its driving members in the same positions relative to each other as most of the other models, but it is distinctive in having, apparently, the fork drive instead of the central shaft. That is, as is sometimes on the French Acatene and in the models with the Sager pin-roller gear as thus far made, the driving shaft is tubular and takes the place of the usual fork, carrying the pinions on its ends, while the stay is a stout rod paralleling this shaft and within it, running from crank axle to wheel hub and fastening at each end with a nut. The lefthand side has a similar stay rod within the fixed tube, so that the frame is especially stiff. The wheel hub has twenty-four teeth and the shaft has twenty-three at the rear, as usual; but at the front are eighteen, driven by forty-eight. As the Crawford chainless is under license from the Pope Company, some comment has been caused by its announced price of $75, but the explanation is offered that an exception was made in case of this model because it uses only some of the patents held by the Pope Company.
THE DAYTON CHAINLESS.
The [Dayton chainless] has been already described, but we are now able to furnish cuts. It is of the locomotive or double-crank construction, substantially as shown two years ago under the name of the Loco or Twentieth Century. A double-flanged notched pulley, with a link belt, equivalent to a centrally notched sprocket and chain, runs within the crank bracket, working centrally and tightly enclosed. This is necessary to obtain speeding up and to preserve motion in the forward direction. Adjustment of tension is by an eccentric on the crank axle. The small pulley is one piece with a pair of short cranks set at right angles or quartering, and these work connecting rods, whose length is slightly variable when necessary by means of an eccentric adjustment at the forward end. Every bearing is a ball bearing, of course. The rear forks are of D tubing, and narrowness of tread is further attained by “cranking” the connecting rods, the portion thus bent being reinforced to avoid weakening. For this type of chainless the following is claimed:
THE DAYTON CHAINLESS.
“Its most important advantage is derived from the equal transmission of motive power on both sides of the frame from the crank-hanger to the rear hub. This equal division of power transmission is both constant and continuous. Not only is much of the friction of a bevel-gear eliminated, but the danger of springing the rear fork out of line by a sudden strain is completely removed. All bearing points of the transmitting mechanism are encased and made absolutely weather proof.”
Whatever view is held regarding the mechanical advantage or disadvantage of this method of transmitting power for bicycle purposes, there can be no doubt that there is some benefit from the alternation of driving strains from one side to the other, instead of having them only on one side, and also that the complete inclosure of the driving parts is a benefit. But users of this type of bicycle must learn to mount without a step, since none can be fitted, on account of the crank action on the rear wheel.