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 performance and testing of Borg & Beck clutches on Bentley cars.
| Identifier | ExFiles\Box 129\2\ scan0114 | |
| Date | 16th August 1935 | |
| COPY. To E.{Mr Elliott - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} c. to Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} c. to Hdy.{William Hardy} Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}8/KW.16.8.35. Bentley Clutch. We now have two cars, B-23-AE and 1-B-IV, running with 10" Borg & Beck clutches fitted to a flywheel as suggested by them and shown on Ex.18198. Both cars are exceedingly good as regards smooth take up and both are free from the usual engine period at 3800 r.p.m. The latter we ascribe to the exceedingly stiff section of the flywheel flange. It has always been our practice to use a flexible flywheel so that the critical speed of the flywheel is at such a low speed that the disturbing forces do not excite it to any great extent. The Borg & Beck flywheel shows apparently that the vibrations can be got above the running range. We have submitted the clutch on 1-B-IV to the same destruction test as was carried out on 19-C-IV (fabric on driving member) and the Buick. This test consisted of about 1100 starts on top gear. On 19-C-IV the total lining wear was .041", on the Buick the linings were worn to the rivets, on 1-B-IV the lining wear amounted to about .003". We shall fit one of these clutches to 6-B-IV for a 10,000 miles test on the large bore unit. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||