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Vol (II the handle-bar)

II the handle-bar to the backstays by the most natural route, viz., by the top tube. Its drawbacks are that the wide curves of conduit look untidy, and that as the cable is hidden from view it may fray and break without the rider having any knowledge of what is happening. This, however, is, under proper conditions, of the rarest occurrence.

A.-BRAKES WITH VISIBLE TRANSMISSION. 106. Hand-applied Front Rim Brake with Roller Levers and Visible Transmission (Fig. 25). - The lever pivots in clips rigidly attached to the handle-bar. When pressure is applied by the hand to the handle of the lever, it rolls round in the clips, and in doing so lifts a bell crank attached to its other end, which in turn lifts the brake-rod. The brake-rod consists of a solid rod, which fits into a tube attached to the horse-shoe. The length of the brake-rod is regulated by sliding this rod in the tube, thus bringing the horse-shoe and with it the brake blocks nearer to or further from the rim. When the correct adjustment is obtained, the tube and rod are locked together by the small set screw. Brakes should be so adjusted that the machine cannot be wheeled when they are applied.

If they are too violent in action (which must be ascertained by experiment) they must be loosened.

It should never be necessary to interfere with the clips attached to the front forks.

The spring which releases the brake is shown at the end of the lever. In a well-known brake (the Crabbe) there is no spring, its place being taken by the natural spring in the horse-shoe. 107. Hand-applied Back Rim Brake with Roller Levers and Visible Transmission. - The lever and brake-rod are similar to those described for the corresponding front brake, except that the set screw which is fitted to the brake-rod serves only for the adjustment of the length of the rod E a the to the height of the handlebar, and that at its lower end instead of carrying a stirrup it communicates with a bell crank, which is connected in its turn with rod running down bottom tube of the frame. At the crank bracket is another bell crank hinged to a short rod which carries the brake stirrup. This lies under the chain stays, to which are fixed clips similar to those used for the front brake. The adjustment of the brake is effected as follows. The short rod above-mentioned consists, like the front brake-rod, of two portions, threaded and united by a long regulating nut (which can be turned with the finger) and a lock nut. The rod can thus be lengthened or shortened and the brake blocks brought further from or nearer to the rim. This is the most convenient type of back rim brake on the market. Its drawback is that as its working parts are so near the road they are apt to become choked with mud, and this is a nuisance when adjustments have to be made. The brake is better placed on the back stays, where is is more accessible and out of the way of mud. At present, however, the only brakes with visible connections which have (ELSWICK.) the stirrup and brake blocks upon the back stays transmit the braking force through rods carried as above to the crank bracket, and thence by means of additional hinges up to the seat lug and down to the back stays. This complicated arrangement is objectionable, because of the excessive multiplication of working parts and resultant friction. It is surprising that no maker carries his brake connections by way of the top tube of the frame straight to the back stays. Till this arrangement is obtainable riders who prefer their back brakes on the back stays would do best to have a Bowden wire along the top tube. (See para. 109.) 108. Foot-applied Back Rim Brake with Visible Transmission. -A clutch similar to the ordinary free-wheel clutch is fitted to the crank bracket. When the rider pedals forward this clutch is out of action, but when he back pedals, he drives back the clutch. This has attached to its under side the short rod which carries the [CYCLING stirrup, which it pulls forward, thus applying the brake. Adjustment is effected in the same way as in the case of the similar hand-applied brake described above (para. 107).