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Rh also bolted to the U rims by T-shaped bolts moulded in the rubber, with the tail of the T passed through the rim, being nutted underneath the rim. The average size of solid india-rubber tyres was ¾ in., but sizes from ½ in., for racing machines, to 1¼ in. for roadsters were used. The larger sizes were, however, too heavy.



The first attempt to provide more comfortable tyres for cyclists was by the introduction of the cushion tyre. This was a hollow rubber tyre varying from 1¼ to 1½ ins. diameter, the hole through the centre varying from about ⅜ in. to ¾ in. If the hole was small the tyre was heavy and the machine ran "dead"; if large, the sides pressed hard against the edges of the rim and cut through. Some cushion tyres were more like a glorified thick garden hose, and various shaped rims were introduced to obviate the tendency there was to cut through at the sides. The expense of india-rubber resulted in great