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 rolling resistance and distance rolled from rest for two different tyre types at various inflation pressures.
| Identifier | ExFiles\Box 53\3\ Scan008 | |
| Date | 6th January 1927 guessed | |
| contd :- -6a- GRAPH 1: MACHINE TESTS ON ROLLING RESISTANCE FIG 1. SPEED 50 M.P.H ROLLING RESISTANCE LBS WT/TN INFLATION PRESSURE LBS/SQ IN. 33 x 6.75 TYRE 33 x 5 TYRE GRAPH 2: DISTANCE ROLLED FROM REST YDS ROAD ROLLING RESISTANCE TESTS FIG: 2. INFLATION PRESSURE LBS/SQ IN. 33 x 6.75 TYRES 33 x 5 TYRES | ||