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

OVERHAULING A BICYCLE 23 If the conditions were reversed—that is to say, a lf-in. bracket and a lf-in. hub chain line—it would not be so bad, as it is the practice of some makers to set the machine so that a straightedge held against the outside face of the bracket wheel will be y1^- in. “ off ” the face of the hub wheel 5 the theory being that when pressure is applied to the pedals, the small amount of spring in the back part of the frame will bring the chain line correct when riding. If the back forks are set so that the chain wheels are in line, the difference will not matter a great deal. Determining Length of Cycle Chain. To find the correct length of a chain, multiply the distance from the centre of the bracket axle to the centre of the back wheel axle by 2. Add together the number of teeth on the bracket wheel and hub wheel and divide by 2 ; add these two results together, and the result will be the length of chain required in inches, if the chain is 1-in. pitch. If |-in. pitch, do not divide the combined number of chain wheel teeth. Thus, for example, wheel centres 19 in., bracket wheel 24 teeth, hub wheel 8 teeth * (19 X 2) + —= 54 m.j which is the length of chain required for 1-in. pitch. Replacing Block Chain with Roller Chain. The advantages of a roller chain (see Figs. 14 and 15; over an old-fashioned block chain are : less friction on the chain-wheel teeth and quieter running ; while in rainy or dirty weather a roller chain does not get stiff and mount the teeth as a block chain will. The +in. pitch roller chain is the one most in favour, but this will not fit a