Page:The Cycle Industry (1921).djvu/53

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around angles which are not too acute to prevent free sliding of the wire inside the cable.

Another popular type of brake is the roller lever brake. This is usually made up by the cycle maker to suit his own models and consists of a lever placed each side of the handle-bar which rolls or turns in a bearing. At each end of the lever there is a crank which pushes down a rod in communication with the front or rear brake shoes. The handle-bar brakework is usually assembled on the bar ready to slip into the machine in the finishing shops.

Handle-bars are largely bent by specialists, but some firms make their own. The process is usually to bend the touring patterns cold by inserting a spring mandrel in the straight tube, to prevent the metal kinking or denting, and withdrawing the mandrel by unwinding it. The curly types of handle-bar affected by racing cyclists often have to be filled with sand or rezin prior to heating and bending, the "loading" material, as it is called, being afterwards melted and poured out.

The stem of the bar may be inserted in a "T" lug threaded on the bar, or it may be made entirely from steel tube. In the latter case some skill is required to wrap or "lap" the top of the split stem around the bar to make a neat joint. Seat pillars are nearly always made by the "lap" joint method; a good bicycle may be often known by a careful examination of these joints, because a maker with a reputation employs men who can make these joints practically invisible, whilst the shoddy ones have rough edges and imperfectly made joints.

As the polishing, plating, and enamelling have to take place before the machine is assembled, we will visit those shops before going to the finishing shop, the term applied to the bay or floor, where the bicycle receives its final touches.