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).
Brake leverage, piston design, engine rings, and balance weights for a new car series.
| Identifier | ExFiles\Box 16\1\ Scan127 | |
| Date | 5th May 1913 | |
| X741 COPY. R5/B5.5.13. Sheet 2. *293 It was unnecessary resistance to the application of the brake and somewhat misleading in adjusting the brakes- with this removed I think that we can do with less leverage and, therefore, either more clearance or less frequent adjustment. Will Mr. Bailey arrange experimentally to reduce the leverage from 10% to 25%. I think that for the present we had better retain the countershaft since it increases the elasticity so little, as it will help us in several other ways, including the provision of a better adjustment of the pedal (Driver's adjustment) this must be limited both in taking up and letting out. Convenient and secure suggestions to follow PISTONS. These are of the light cast-iron type and seem exceedingly good- they have the substantial diagonal double webs and long boss. If similar ones could be made in steel with dished tops I should think that they were very satisfactory- this should be tried in 4 1/2" and 4" diameter. RINGS. Comparing this engine with the one sent out at Christmas, one is struck by its superior slow running properties - which, I believe, is caused by the superiority of either the fit or type of rings - the superior ones being of the double type with the new solid location between the rings. BALANCE WEIGHTS. With the good pistons and rings these do not seem to influence the lubrication and the whole car seems quite free from vibration except the one occuring at 22 miles per hour which has been shewn, experimentally, to come from the reaction of the engine in the frame and with which we have not yet found a way of dealing except theoretically. The crankshaft bearings must wear better with these balance weights fitted and they must increase the mechanical efficiency and account for some of the good performances with so low a compression, small induction pipe and carburetter. Additional report to follow re changing of gear, rear tank etc. This is the first car on the lines of series 2700. Perhaps the Directors would be interested. F.H.R. COPY. | ||