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).
Starter motor gearing ratio and starting speed.
| Identifier | ExFiles\Box 64\1\ scan0111 | |
| Date | 12th April 1923 | |
| To EFC. from E.{Mr Elliott - Chief Engineer} c. to CJ. X9620 E2/M12.4.23. X.9620 - STARTER MOTOR EFCL/T9423. In reply to your EFCL/T9423 we should be glad if you could come down to WW. on Thursday next the 19th inst., bringing the data you mention. Regarding the question of the ratio of the starter gearing this matter has been carefully considered by Mr. Royce and he fully intends to adopt a larger ratio than 23.3 to 1 with a view to using the weight of material in the motor to a greater capacity. The trouble with the larger ratio was not forgotten but this motor will be smaller and lighter and the design should be made suitable for high speed and quick acceleration. Regarding the speed of the engine when starting Mr. Royce does not favour increasing this as an increased speed is not of very great benefit and has the disadvantage of demanding a heavier battery. Nevertheless with a lighter flywheel and probably somewhat higher compression it may be advisable to put the revs. up 25% which means the engine would turn at 55 R.P.M. and the motor 1760 R.P.M. E.{Mr Elliott - Chief Engineer} | ||