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 results for a 20/25 starter motor drive fitted with a stronger spring to prevent slipping.
| Identifier | ExFiles\Box 40\5\ Scan208 | |
| Date | 22th January 1931 | |
| E.7.C. Ref No WE75 X3587. Date 22-1-31 X.Nos 5620 3587 R.R. 20/25 Starter motor drive We have tested another 20/25 starter motor fitted with a stronger spring in the Bijur drive in order to prevent undue slipping when starting the 20/25 cold. The current, gradually raised, which will cause the drive to slip was found to be 236 amperes. The current, switched straight on, to cause the drive to slip was 176 amperes. HEwest | ||