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MOTORS AND MOTOR-DRIVING
has shown, however, that the security of this tyre at speeds in excess of sixteen miles an hour is a doubtful quantity. The tyre shows a tendency to become detached from its bolts, and as it is very heavy it is likely to be lifted off by centrifugal force.
In the case of solid tyres the chief essential is that a gap of a quarter of an inch should be left between the ends, to allow of expansion under heat or pressure. If this gap becomes closed in time one end of the tyre should be cut away. If the tyre be a close fit at the outset it will creep on the rim, crack at the sides, and be liable to fly off at any but slow speeds.
