on normal or middle, and three to three and a half turns of the road wheel on top gear, the machine moves faster with approximately the same exertion; or to explain it another way, the rider has no need with a high gear in use to exhaust himself with rapid pedalling as he would do if he wished to ride fast with a normal single gear.
Some racing cyclists disdain the change speed gear and prefer a single gear of medium ratio, but for tourists, and particularly for women and elderly men, the change speed gear is a boon.
Fig. 19 |
Ever since the days of the first safety bicycle the advantages of a change speed gear have been recognized, but it was not until about 1900 that a practical device was marketed. Previous designs were either too heavy and complicated or their poor construction caused so much friction when the train of gear wheels was in use that cyclists preferred a single gear.
I think it was at the Stanley Show of 1900 that Linley and Biggs exhibited a change speed gear that was made by running a specially shaped chain over chain wheels that were wide enough to allow a lateral movement of the chain to shift it from a small to a big sprocket on the rear hub. This provided a change