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).
Data table comparing flywheel and clutch specifications for various engine configurations.
| Identifier | ExFiles\Box 130\3\ scan0123 | |
| Date | 28th February 1940 guessed | |
| FLYWHEEL DATA 6 CYLINDER ALUMINIUM - B.60 AND B.80 ENGINES AND R.R. STARTER MOTOR. TABLE DATA: COLUMN 1 - ITEM: ENGINE CLUTCH INERTIA - LBS·INS² OF COMPLETE FLYWHEEL CLUTCH INERTIA COMPLETE TOTAL INERTIA % INERTIA RATIO 11" CLUTCH % INERTIA RATIO 10" CLUTCH WEIGHT OF FLYWHEEL COMPLETE - WITHOUT CLUTCH % WEIGHT RATIO 11" CLUTCH % WEIGHT RATIO 10" CLUTCH CAR USED ON REMARKS COLUMN 2 - ALUM - 6 CYL: CLUTCH: 11" LONG or B.B INERTIA: 1580 CLUTCH INERTIA: 450 TOTAL INERTIA: 2030 % INERTIA RATIO 11" CLUTCH: 100% WEIGHT OF FLYWHEEL: 51 LBS % WEIGHT RATIO 11" CLUTCH: 100% CAR USED ON: STANDARD PRODUCTION REMARKS: RIGID FLYWHEEL FOR BASIS OF COMPARISON. COLUMN 3 - ALUM - 6 CYL: CLUTCH: 10" INERTIA: 1580 CLUTCH INERTIA: 250 TOTAL INERTIA: 1830 % INERTIA RATIO 10" CLUTCH: 100% WEIGHT OF FLYWHEEL: 51 LBS % WEIGHT RATIO 10" CLUTCH: 100% COLUMN 4 - C.I. - 8 CYL: CLUTCH: 11" LONG DIAGRAM PART NUMBERS: RM{William Robotham - Chief Engineer}·576 or G.B. 5290, RM{William Robotham - Chief Engineer}·574 or G.B. 5292, RM{William Robotham - Chief Engineer}·575 G.B. 5291 INERTIA: 1628 CLUTCH INERTIA: 450 TOTAL INERTIA: 2078 % INERTIA RATIO 11" CLUTCH: 105% WEIGHT OF FLYWHEEL: 43 LBS % WEIGHT RATIO 11" CLUTCH: 84% CAR USED ON: 11-B-5, 30-G-7, 33-G-7, 4-B-50. REMARKS: R.R. STARTER MOTOR COLUMN 5 - ALUM-6CYL STD: CLUTCH: 10" LONG DIAGRAM PART NUMBERS: RM{William Robotham - Chief Engineer}·569 G.B·4758, G.B·5013, G.B·5293 INERTIA: 1470 CLUTCH INERTIA: 250 TOTAL INERTIA: 1720 % INERTIA RATIO 10" CLUTCH: 94% WEIGHT OF FLYWHEEL: 43.5 LBS % WEIGHT RATIO 10" CLUTCH: 85% CAR USED ON: 6-B-5, 7-B-5, 8-B-5 REMARKS: B-5 STANDARD R.R. STARTER COLUMN 6 - ALUM-6CYL LT: CLUTCH: 10" LONG DIAGRAM PART NUMBERS: RM{William Robotham - Chief Engineer}·570 G.B·5206, G.B·5013, G.B·5293 INERTIA: 1088 CLUTCH INERTIA: 250 TOTAL INERTIA: 1338 % INERTIA RATIO 10" CLUTCH: 73% WEIGHT OF FLYWHEEL: 32.4 LBS % WEIGHT RATIO 10" CLUTCH: 64% CAR USED ON: 14-B-5. REMARKS: "CORNICHE" R.R. STARTER COLUMN 7 - C.I.-6CYL STD: CLUTCH: 10" LONG DIAGRAM PART NUMBERS: G.B·4918, G.B·5013, G.B·5293 INERTIA: 1477 CLUTCH INERTIA: 250 TOTAL INERTIA: 1727 % INERTIA RATIO 10" CLUTCH: 94% WEIGHT OF FLYWHEEL: 39.5 LBS % WEIGHT RATIO 10" CLUTCH: 68% CAR USED ON: 3-B-50. REMARKS: HEAVY R.R. STARTER COLUMN 8 - C.I-6CYL LT: CLUTCH: 10" LONG DIAGRAM PART NUMBERS: RM{William Robotham - Chief Engineer}·572, G.B·5013, G.B·5293 INERTIA: 1088 CLUTCH INERTIA: 250 TOTAL INERTIA: 1338 % INERTIA RATIO 10" CLUTCH: 73% WEIGHT OF FLYWHEEL: 31.4 LBS % WEIGHT RATIO 10" CLUTCH: 62% REMARKS: LIGHT R.R. STARTER | ||