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).
The gear reduction ratios for an EAC starter motor.
| Identifier | ExFiles\Box 68\3\ scan0164 | |
| Date | 19th January 1925 | |
| EFC. X8640 19.1.25. X. 8650. X. 8640. EAC. STARTER MOTOR REDUCTION. The new reduction is as follows :- Epicyclic gear of the motor 4 to 1 = 4 to 1 Motor pinion to flywheel. 65 to 9 = 7.222 to 1 Total reduction. 260 to 9 = 28.89 to 1 CAP. | ||