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).
Comparative table of brake efficiency test results for various electric starter motors.
| Identifier | ExFiles\Box 61b\3\ scan0057 | |
| Date | 28th April 1917 | |
| MOTOR:- | Lucas. A.510. | C.A.V. | R.R.45 | R.R.17. | R.R.24. | Bosch. | Bijur. BRAKE EFFICIENCY TEST RESULTS MAX. POWER B.H.P+ | 1.40 | 1.33 | .815. | .740 | .660 Speed (R.P.M.). | 1135 | 900 | 880 | 1050 | 880 Torque (lb-inches) | 78 | 94 | 58 | 45 | 52 Volts. | 8.55 | 8.3 | 9.9 | 10.2 | 10.4 Amps. | 212 | 260 | 122 | 111 | 105 "fficiency | .58 | .47 | .505 | .495 | .445 MAX. EFFICIENCY Efficiency | .695 | .675 | †628 | .535 | .545 B.H.P. | 1.12 | .95 | .58 | .665 | .46 Speed (R.P.M.) | 2020 | 2420 | 1720 | 1410 | 1730 (handwritten) Torque (lb-inches) | 35 | 25 | 21 | 30 | 17 Volts. | 9.9 | 10.0 | 10.8 | 10.4 | 11.1 Amps. | 122 | 105 | 63 | 90 | 57.5 Starting rush of current (approx). | 400 | 400 | 250 | 225 | 250. Margin Text (Top Right): R.R. 235A. (500 'D') (S.D. 408. 28-4-17.) Bm 2/156/13. | ||