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 testing and comparison of Bendix and Bijur starter pinions and flywheel gears on a Liberty car.
| Identifier | ExFiles\Box 40\5\ Scan103 | |
| Date | 19th December 1922 | |
| Oyl-W-121922 -2- finally to touch the flywheel edge before the parts D-50887 and D-50886 (R.R. nos.) come together. The motor then spins round, pressing the clutch disc between parts D-50886 and D-50895, but without turning the engine, because of lacking the final screw lock against the collar D-50887. This defect did not show up until after 13,500 miles and was entirely our own fault. Use on Liberty On the Liberty car which we have at the works for general duties, we ran 17,000 miles on a cast iron flywheel gear which had already been so badly damaged by a Bendix pinion that it jammed about once in every two tries. The Liberty is six cylinder 3 1/8" x 5", geared about 11 to 1 on the starter. We used a 5" Bijur motor which had been a sample submitted by Bijur to the Liberty Company when they started in business, but rejected by them on the score of cost. (The Bijur Company favor the larger motors on the score of the lower speed characteristics which are possible, which avoid violent slamming of the teeth). After 17,000 miles, the flywheel was too badly damaged to continue. On replacing this with a new flywheel gear (still cast iron), we have run now a further 11,000 miles without trouble. We have never had any trouble with the pinion in this 28,000 miles of use, making a very large number of starts because of the use to which the car is put. Bijur recommendations a - Small pinion - One of the principal claims of superiority made by the Bijur Company is that their pinion as compared with the Bendix pinion can have a fewer number of teeth, because the shaft can be only 5/8" diameter, instead of about 7/8" with the Bendix in order to allow depth for cutting the thread, and also because very little need be left below the teeth in the Bijur pinion since it is driven from the ends of the teeth, not through the root of the teeth. The standard S. A.{Mr Adams} E.{Mr Elliott - Chief Engineer} pinion has 11 teeth, but Bijur | ||