Page discussing Rapson double-tread tyres and the effect of balloon tyres on petrol consumption, including a performance graph.
| Identifier | ExFiles\Box 158\1\ scan0014 | |
| Date | 14th January 1927 guessed | |
| contd :- -6- tread makes the tyre ride very harshly when new. In addition, on the Rapson double-tread tyre, when the first tread, [handwritten: when] <s>tread is finished</s>, [handwritten: worn out], it comes off in a series of large pieces which hit the wings of the car and make a tremendous noise. As this continues for many miles it is rather a distressing feature. III: PETROL CONSUMPTION AND TYRES. (a) The effect of balloon tyres on consumption. Balloon tyres are often accused of causing a considerable increase in petrol consumption. We give the results of a test carried out on cord tyres shewing the measured difference in consumption when these are run first at an absurdly high, and then at an exceptionally low inflation pressure. [GRAPH SECTION] TYRE INFLATION PRESSURE EFFECT OF SPEED & TYRE PRESSURE ON PET. CONSUMPTION WATER TEMP 80°C. IGNITION STANDARD MIXTURE CONTROL CENTRAL AXLE 15 x 52 TYRES STANDARD [Y-AXIS LABEL] PET. CONS. MPG [X-AXIS LABEL] ROAD SPEED MPH [GRAPH LEGEND] 60 Lbs/□" [GRAPH LEGEND] 25 Lbs/□" It will be observed that at a normal touring speed of 30 m.p.h. this amounts to about 6%. Now the difference between the rolling resistance of a normally inflated high pressure and balloon cord tyre is less than that contd :- | ||
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).