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).
Comparison of Rudge and Bentley engine features and performance, including notes on supercharged running tests.
| Identifier | ExFiles\Box 133\1\ scan0113 | |
| Date | 17th September 1936 | |
| -9- (1) The Rudge has all ball or roller bearings, thus reducing bearing friction. (2) Large piston clearances, and only two narrow rings reduce piston friction. (3) Large valve area/litre gives reduced pumping losses. (4) No complicated camshaft or timing mechanism. (5) No water pump, and only a very small oil pump. Fig. XXXII gives a comparison of 1.M.E.P. for the Bentley single cylinder unit, and the Rudge motor-cycle engine with Rudge and Bentley timings, when it will be seen that at high speeds the Rudge gives a considerably better 1.M.E.P. A discussion on this point will be entered into later. Supercharged Running. Quite a lot of work has been done in this section, but great difficulty was experienced due to mechanical failures which held the job up very considerably. These will be gone into in detail later on. Originally it was desired to compare the performances of air and water cooled units, but all that was managed was the air cooled performance on two camshafts - Rudge and Bentley - and a few figures from the water cooled job. | ||