Chapter 12

Motor Bicycles

The motor bicycle, it must be confessed, is in a state of transition, notwithstanding a vast amount of ingenuity and money has been expended on it; the advantages are obvious. There seems no reason why it should not be sold at a little more than double the price charged for an ordinary, well made strong bicycle.

The advantage of requiring so little house room, and being stowed away in a railway luggage van, must outweigh many disadvantages. The chief disadvantage seems to be side-slip - dangerous on an ordinary safety bicycle, but more dangerous and frequent on a motor bicycle, on account of the extra weight.

In one of Daimler’s early patent specifications he shows a machine with wooden wheels of the type ridden in the early seventies, and then known as the ‘‘ boneshaker,” with a petroleum engine driving the rear wheel by a belt, which was tightened by a jockey pulley to cause the engine to drive. About 1894 the Wolfmuller appeared - a very ingenious machine, but much too heavy; two slow running petroleum engines worked direct on to cranks, on the axle of the rear wheel. If report be true, this machine was difficult to start, and sometimes difficult to stop. It seems now to have quite disappeared.

The Werner seems to have attained a fair degree of popularity. A photograph of one (an early type) is shown in fig.39. A very light engine of the De Dion type is fitted above the steering fork just below the handle-bar; a small grooved pulley is on one end of the crankshaft. This carries a leather band, which drives on to a grooved wheel fastened to the spokes of the steering wheel. The engine is started by pushing the cycle along, or by mounting it and pedalling it as an ordinary bicycle. To enable this to be done a lever is so arranged to hold open the exhaust valve to reduce the labour of working the engine against the compression, as in a motor tricycle. On the exhaust valve being released, the mixture is fired and the engine drives the machine. Like the motor tricycle, it is fitted with a freewheel, but on hills the rider must assist the motor by pedalling. The driving belt is of twisted leather, the ends being joined by a steel hook. To take up the slack, the ends are unhooked and one or two extra twists are given to one end of the belt, and the ends then hooked together. If the engine becomes disabled, the belt is unshipped, and the rider pedals it as an ordinary bicycle.

The early Werners were fitted with tube ignition, but this has given place to electricity, the firing gear being very similar to that of the motor tricycle, the carburetter, petrol tank, and accumulators being carried in the space between the tubes of the framing. The Werner has been ridden by Mr. Joseph Pennell through France and Switzerland, and over some of the Alpine passes. One objection to the present type appears to be the difficulty in starting on an up grade. It seems that this might be easily got over by starting engine by hand, and tightening the belt by a jockey pulley, as suggested by Daimler in his early patent alluded to above. Another objection seems to be the centre of gravity is very high, and the chief weight being above the steering-pillar must render the steering far more difficult than that of an ordinary safety bicycle.

The Minerva bicycle is shown in figs. 40 and 41. It has been introduced into this country from Switzerland. The engine is below the frame, and clamped to the lower tube of the bicycle. The engine, with carburetter, is so made that it can be fitted to any strongly made bicycle. The driving gear is similar to the Werner, the motion being communicated to the rear wheel by a twisted leather band.

The engine is lighter and of less power than the Werner. All the parts are very light, but appear to be well proportioned for the work they have to do.

The Singer motor bicycle is an entirely new departure, the whole of the machinery being inside the rear wheel (see fig. 42). The rear wheel is not of the ordinary cycle type, but is composed of two dished aluminium plates, cut away to form spokes, leaving a space of about seven or eight inches for the whole machinery - engine, carburetter, petrol tank, ignition apparatus, and gearing. The speed of the engine is controlled by one lever attached to the handle-bar, from which a rod runs back to the centre of the driving wheel, where it gives motion to a short lever, which operates all the required motions, lifting exhaust, and controlling air and gas supply. The ignition is electric, by the Simms - Bosch magneto machine, to be described in Chapter 16. It is impossible to fully describe this undoubtedly ingenious machine without drawings, which are not available, but in the writer’s opinion the difficulty in getting at the working parts to do any slight repairs or adjustments, which are inevitable in almost all machinery, may prove a slight drawback to its use, though it is but fair to add the engine requires astonishingly little attention.

Trailers of all kinds are used with motor bicycles, and some types have specially powerful motors, so that they shall be equal to the extra haulage.