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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).
Proposed alterations to the 40/50 front braking system and comparing different schemes.

Identifier  WestWitteringFiles\Q\December1926-January1927\  32
Date  9th December 1926
  
To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}
c. C. J.{Mr Johnson W.M.} Wor.{Arthur Wormald - General Works Manager} Da.{Bernard Day - Chassis Design}
c. Re. E.{Mr Elliott - Chief Engineer} By.{R.W. Bailey - Chief Engineer}
c. Ov.

Hs{Lord Ernest Hives - Chair}/Rml/T9.12.26.

X8420
X8370

REDUCED FRONT BRAKING.

We are sending you a graph of the proposed alter-
ations to the 40/50 braking. In our opinion altering the
servo levers will not reduce the proportion of front braking
sufficiently. Also we do not think that on the whole the
pedal pressure on the 40/50 is too light, and therefore would
[struck through text] rather not reduce the rear braking units. With
reference to wear on the servo, this has never caused the
least trouble. If it is made less efficient, the driver will
merely push harder which will inconvenience him and produce
the same unit pressure on the servo. We consider that the
factor dictating the load on the servo plates is the pull
from the servo required to lock the rear wheels. Altering
the leverage between the pedal and the servo does not decrease
the amount of work that the servo has to do. We are trying
out shortened cam levers on the servo, but consider that even
if found desirable, they should be fitted with long levers on the
front brake countershaft to reduce the percentage to the front.

Scheme. % Front braking. Total braking units
for unit pedal press.
1. Present standard. 40.5% 2080.
2. Da{Bernard Day - Chassis Design}2/Ml 226. 38.7% 1720.
3. Expl. Mod. 34% 1860.
4. 2 & 3 combined. 32% 1550.


7-EX. car which has gone to Le CanadelHenry Royce's French residence is
arranged with Scheme 3.

Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}
  
  


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