From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Two graphs comparing the rolling resistance of different tyres against varying inflation pressures, both in machine tests and on the road.
| Identifier | ExFiles\Box 45\2\ Scan009 | |
| Date | 1st January 1927 guessed | |
| contd :- -6a- Top Graph: Title: MACHINE TESTS ON ROLLING RESISTANCE FIG 1. Subtitle: SPEED 50 M.P.H Y-axis: ROLLING RESISTANCE LBS W/T TN X-axis: INFLATION PRESSURE LBS/SQ. IN. Curve 1: 33 X 6.75 TYRE Curve 2: 33 X 5 TYRE Y-axis values: 50, 40, 30, 20 X-axis values: 20, 30, 40, 50, 60, 70, 80 Bottom Graph: Title: ROAD ROLLING RESISTANCE TESTS FIG: 2. Y-axis: DISTANCE ROLLED FROM REST YDS X-axis: INFLATION PRESSURE LBS/SQ. IN. Curve 1: 33 X 6.75 TYRES Curve 2: 33 X 5 TYRES Y-axis values: 1120, 1110, 1100, 1090, 1080, 1070, 1060, 1050, 1040 X-axis values: 20, 30, 40, 50, 60, 70, 80 | ||