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).
Test report on a 25 HP engine's double rear crankshaft flywheel bearing.
| Identifier | ExFiles\Box 137\4\ scan0333 | |
| Date | 4th May 1931 guessed | |
| Copy for Files. 25 HP. FLYWHEEL DOUBLE BEARING. We have now tested the double rear crankshaft bearing on IV.G.6 Japan unit in 12.G.IV. chassis. This bearing definitely eliminates the flywheel period at 3100 rpm. but the engine gets progressively rougher after 3000 rpm. being very rough at 3700. Between 40 and 45 m.p.h. on top gear the engine was noticeably rough especially on the overrun. The engine mounting for this test was the standard 25 Hp. mounting, the Y. bracket not being in use. Before the road test this engine had done about 10 hrs. running for power curves on the test bed. The bearing proved to be in good condition after this. The double bearing certainly removes the flywheel vibrations, but does not make the engine smoother at very high speeds. Other engines in other chassis are smoother after 3000 rpm. than this one. | ||