Cycle Repairing and Adjusting
With a Chapter on building a Bicycle from a Set of Parts

FREE WHEELS AND COASTER HUBS 109 portion screwed to the hub is made from a solid forging, with a ball-race formed on the inner side, the opposite side being screwed for the purpose of receiving an adjusting cone or washer. The balls form a bearing upon which the chain ring revolves. The outer cone is locked against the face of the portion of the clutch screwed to the hub. .Fig. 47 clearly demonstrates the manner in which the drive is effected. The two pawls are each supported by a light spring ; this spring throws the pawl into the rack machined inside the chain wheel. When the wheel is being driven by the pedals, the pawl fits into one of the teeth, with the result that the whole of the clutch mechanism revolves together. When free-wheeling, the chain ring is held stationary, and the inner portion of the clutch carrying the pawls then overruns the chain ring. The Micro free-wheel employs rocking pawls, and is a pattern that has long given satisfaction. Coaster Hubs What is known as a “ coaster hub ” is a combination of rear hub, free-wheel clutch, and pedal-operated brake. It allows of safe “ coasting,” inasmuch as the brake is of an extremely strong and efficient pattern. This type of hub has now become extremely popular, and there are many different makes on the market from which to choose. It is much simpler to remove a back wheel fitted with a coaster hub than when rim brakes are employed, the brake shoes of the latter causing trouble. A coaster hub will be found an ideal brake for a road-racing machine fitted with wooden rims, as the rubber blocks of a rim