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).
Changes to front and rear braking proportions and test results.
| Identifier | ExFiles\Box 41\1\ Scan102 | |
| Date | 15th February 1927 | |
| -2- February 15, 1927. Roughly speaking therefore, for a given effort of the foot, Derby originally had - 40% front braking - 60% rear braking Now have - 30% front braking - 60% rear braking We have - 30% front braking - 50% rear braking. Earlier Test. We have been over this ground before (on 12-MC in November 1925), having reduced the front braking in the same proportion as England has done, by altering a lever on the old "step-over" shaft. After testing for some time throughout last winter we came to the conclusion that there was a considerable increase in the tendency to skid at the rear, and therefore that it was desirable to reduce the rear braking also by reducing the total servo effect. Oy. MO/E | ||