P. and M., No. 87.
An old favourite which is sure to attract all visitors to the Show is the chain-driven two-speed P. and M. In these days of change speed gears it is well to recollect the fact that the P. and M. was the first motor cycle to be fitted with a two-speed gear as a standard feature, which proves the foresightedness of the designers. The 2½ h.p. light model is the latest creation of the firm, and is best described by stating that it is a miniature example of the popular 3½ h.p. model except that the engine has an automatic inlet valve.
Control is now by inverted levers on the handle-bar, and the carburetter is governed by the new Bowden handle-bar levers, these are not clamped to the bar, as on most machines, but are attached by screws, which protrude through the centre, so preventing any possibility of their moving. The wires themselves are enclosed in the bar, and give this part of the machine a very clean appearance. The lubricating pump is inclined, and has a celluloid barrel. The rear number plate acts as a mudguard stay. The chains from the engine to counter-shaft are enclosed. Lubrication is afforded to these chains by means of a small pipe extended from the ball release valve, so that any escape of oil is directed on to the chains. The exhaust pipe is large, and has only one gradual bend. The usual handle starting arrangement through the low gear is retained by means of a half compression arrangement operated by studs on the footplate. The lubrication of the wedge bar clutch bearing has been rendered much more simple, as a pear-shaped window can easily be slid upwards, directly exposing the portion to be lubricated.
On the same stand is a Colonial model, with 6in. clearance under all, which is stronger in build, and is designed to conform to the special requirements of Colonial motor cyclists. The spring forks have triple girders, and 2½in. tyres are fitted. A larger tank is also provided. In addition to the usual engine chain case, there is another guard for the rear chain on the Colonial model, which, by the way, may be fitted as an extra to the standard machines.
Phelon & Moore Two-speed Gearbox
The original form is undoubtedly the Phelon & Moore, which is shown at Fig. 183. The low-gear sprocket, which is the largest, is the outside member, while the high-gear sprocket, which is the smaller of the two large ones, is the inside member. The clutch members act as bearings on which the sprockets revolve when the gear is in neutral position, but when expanded the shoes grip the interior of the drum carrying the sprockets very tightly and transmit the power to the small sprocket to which the brake shoes are fastened. The internal clutches are brought into engagement by sliding a wedged-shaped member to the right or left as the case may be, and spreading out the brake shoes. In the form shown at Fig. 183, if the wedge bar is moved to the right, the brake shoe that clutches the high speed sprocket will be expanded, and the drive will be from the engine shaft to the countershaft through that member, while the low gear or larger sprocket will revolve freely on the brake shoes that are not expanded and which therefore act as a bearing for that member. If the wedge bar is moved to the left, the outside sprocket will be clutched to the driving member, and the smaller or high-gear sprocket will revolve freely on its brake shoes. It would seem that there would be considerable wear due to the movement of the sprocket carrier over the brake shoes, but the successful use of this form of change-speed gear for a number of years indicates the large surface of the bearing and the provisions made for lubricating them are adequate to prevent untimely depreciation.
Motorcycles Sidecars and Cyclecars, 1914, by Victor Page
