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).
Comparing two notable alternative starter motor pinion designs and their performance.
| Identifier | ExFiles\Box 40\6\ Scan034 | |
| Date | 23th May 1922 guessed | |
| Cy2 - G 23522 Sheet #2 There are two notable alternatives. The first in ease of operation, but not in virtue, is the Bijur improved Bendix pinion, illustrated in the enclosed print, and of which E.P.,E.F.C. and others have received a good deal of information in the past. Used on 102-CE for about 1500 starts and 5000 miles, this is satisfactory. The ring gear is M.S. At first the motor was high-speed wound, and the clutch in the device was too fierce; as a result the pinion went in with a crash and tore the flywheel teeth up considerably in 600 starts. Since then with a lower-speed winding, as used on our standard motor, and with an easier clutch, the device is good and has done little or no further damage to the teeth. One great argument against contemplating using it is the rocky financial condition of the makers. On the Liberty car belonging to the works, it has run 17000 miles with success, starting with a cast iron flywheel gear which had already been half destroyed by the Bendix originally fitted. The gear has now gone west definitely but that is not a bad performance, considering the already damaged condition of the teeth. The second alternative and the one which we all (and apparently every other maker in the U.S.) feel is the most acceptable scheme to date, is the manual or rather foot-operated pinion shift as used by Delco on the Marmon, Buick, & Essex, and nearly every other decent car which they equip, as now used by American Bosch on the Hudson & Essex, and as being developed strongly by Westinghouse for all their better grade work. You can get full particulars of this from the Delco agencies. For your information, however, I attach prints of the new American Bosch standard outfits on Hudson and Essex. The chief fault with this scheme is that, as generally applied, it hammers badly when the engine swings back from a compression, because this movement locks the free-wheel and kicks the motor armature backwards. Westinghouse provide a spring loaded multi-plate clutch (like our own) to limit the load on the mechanism under this condition. The Bijur shift takes this shock on their friction clutch. | ||