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).
Performance and potential standardisation of Borg & Beck clutches for the 20/25 HP model.
| Identifier | ExFiles\Box 103\1\ scan0206 | |
| Date | 31th January 1936 | |
| X57 W/S - C. c. to Sg.{Arthur F. Sidgreaves - MD} c. to Wor.{Arthur Wormald - General Works Manager} c. to H.{Arthur M. Hanbury - Head Complaints} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/KW.31.1.36. 20/25 HP. Clutches. When Hancock was in London trying out the Borg & Beck clutch under traffic conditions, he confirmed the view that the standard clutch has no chance of standing up when subjected to this type of driving condition. The attached report gives his impressions. Incidentally we have to point out that a Standardisation Sheet was completed on 30.10.34 for a 20/25 HP. clutch having several times the life of the one now giving trouble, but at the time Sales thought it was not so smooth on the take-up and turned it down. It was, however, standardised on the Bentley and two or three hundreds have been fitted with, we understand, almost complete success. We have proved that with a modified type of driven member facing we can get a smooth take-up on the 11" Borg & Beck clutch, and have overcome the trouble we previously experienced on Sg{Arthur F. Sidgreaves - MD}'s car by doing this. Our general experience of the 11" Borg & Beck clutch is that we have been running one on a Bentley for about 12 months experimentally and have had no trouble. We have also done a considerable amount of work in London traffic recently on 21-G-IV, where the clutch has given satisfaction. We have had failures when running prolonged high speed endurance tests on the bench, but we have never been able to reproduce these failures on the road on either the 10" or 11" clutch, and Hancock says that he considers the 10" Borg and Beck clutch on B-56-BN{W.O. Bentley / Mr Barrington} received treatment of maximum severity during the 15,000 miles recently completed. The Borg & Beck clutch saves a considerable amount in cost and weight. We are therefore of the opinion that, having regard to all circumstances, it is worth taking the risk of standardising the 11" Borg & Beck clutch on the big bore 20/25. It would be of assistance to us if Sg{Arthur F. Sidgreaves - MD}'s car could be used as much as possible in London traffic. In the meantime we are doing high speed work in parallel on 21-G-IV. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Att: Hs{Lord Ernest Hives - Chair}/OWN.3/KW.29.1.36. | ||