Page:Popular Science Monthly Volume 90.djvu/789

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Popular Science Monthly


��Operation of the Starter

When the pedal Mis pushed forward, the left arm with the catch F slides down the incline of A, Fig. 5, and is pulled toward the toothed band by the spring E, Fig. 2. The catch engages in the toothed band and the pedal M is given a quick downward push which starts the engine. When the foot is taken off the pedal it is pulled back by the spring C, Fig. 4, and as soon as it starts back the left arm slides up the incline which keeps the catch F away from the toothed band. The arm in this position is shown at P, Fig. 5. This makes it possible to start the engine with the rear wheel on the ground, when the clutch is thrown out of action.

The Footboards

The pedals being removed, it is necessary to provide some support for the feet. To do this, footboards are supplied as follows: A bent bracket is made as shown in Fig. 8. The pieces Q are made of 3^-in. square iron, 73/2 ir*- long, flattened at the upper ends for holes. The piece R is made of iron 1 1 3^ in. long, I in. wide and ^ in. thick, and is riveted to the pieces Q as shown in the illustration.

The piece R should extend about J^ in. at both ends over the pieces Q so as to prevent the hinge of the footboard from turning down. The hinge is shown in detail at 5. The rear bracket is made of the same material as the front. The pieces T and U are fastened together with small bolts at the ends and stove bolts are used on each side of the frame at V. A split wood block W is made to fit in the frame as shown. The front of the bracket on each end will need to be twisted so that its surface will be in the same angle as the footboards.

The general dimensions and shape of the footboards are given in Fig, 9. They are made of hard wood and a rubber cut to the same size and glued to their surfaces. To make a neat finish thin strips of metal are cut about 3/16 in. wider than the thickness of the board and the rubber, and then tacked around the edges. The pro- jecting edge of the metal strip above the board's surface is turned over and on to the rubber top. The front boards are then fastened to the hinge wing with small bolts. The rubber is put on after the boards are bolted to the hinge wings. The front bracket is fastened to the frame with the same bolt that holds the engine, as shown in Fig. 10 and 11.

��The Foot Brake

��The reconstruction of the crank-shaft and clutch leaves the machine without a brake. The brake, which is operated with one foot, is made as follows: The rear sprocket on the right side is removed. A lever is then attached in place of the sprocket to take the end of the brake-rod. The brake-pedal is shown in Fig. 12. The sleeve X is fastened under the engine in front of the square bottom, as shown in Fig. 11. The rod is made of machine steel. The brake- rod should be about 25% in. long. A small hole is cut in the front end of the chain guard for the brake-rod to pass through. The illustration clearly shows the con- struction of the brake parts. The lever Y may appear to be small, but if the brakes work right it requires very little pressure to slide the wheel.

The Foot- Clutch

Another improvement, which is not in- dispensable but is ver>'^ desirable, is a foot- clutch control. The foot-lever for this is shown in Fig. 13, and is applied as shown in Fig. 10. As can be seen, it is attached by the same bolt as the regular clutch-lever. The corners on the outer end of the bolt are ground off and the sleeve of the foot- lever is put on over this. The rod from the clutch runs directly to the control-lever and another rod runs to the regular band lever. A collar Z is put on the foot-lever control rod.

By using the foot-lever the clutch can be thrown either in or out; but with the hand-lever it can only be thrown out, as can be seen by referring to the illustration. These added features to an old style motorcycle have been in use for two years and have given entire satisfaction.

��Iron and Steel Made Rust-Proof with Chemicals

IF iron is placed in a weak solution of phosphoric acid, a coat of insoluble ferrous phosphate is formed on it, which an oxidizing agent makes black and basic. If there is more acid phosphate, salts of calcium, magnesium, barium, or other alkali earth metal in solution, it will react much less violently than when free phos- phoric acid is present. By using hydrated manganic oxide and air as oxidizing agents in the presence of this acid phosphate, a layer of black ferroso-ferric phosphate is formed of suitable thickness, rendering the metal rust-proof.

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