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).
Determination of the minimum tyre size for the B.50 car and conducting skid pan tests.
| Identifier | ExFiles\Box 97\1\ scan0139 | |
| Date | 23th March 1938 | |
| Spare 400 Da.{Bernard Day - Chassis Design} from Rm.{William Robotham - Chief Engineer} Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions} c. Hy.{Tom Haldenby - Plant Engineer} c. Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} c. Rm{William Robotham - Chief Engineer}/ATM. c. Ev.{Ivan Evernden - coachwork} Rm{William Robotham - Chief Engineer}12/R.23.3.38. With reference to Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions}14/R.22.3.38., we consider that it is now up to us to determine what is the minimum size of tyre which we can successfully use on B.50 having regard to the desirable cornering ability of the car. We have a B.III with which we can reproduce the weights, etc. of the B.50. We are, therefore, obtaining all the necessary sizes and types of tyre and carrying out the requisite tests on the skid pan. Since the wheels and tyres are not our responsibility, but are bought from an outside firm, and it is very doubtful that we shall get any reduction of cost by ordering larger quantities, the solution which commends itself to us at the moment is to have a 6½" tyre on both cars, but a 17" wheels on B.50 against a 16" wheel on B.III. We shall be glad to know if Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions} has any objections to this as a final solution if our tests indicate that it is desirable. Rm.{William Robotham - Chief Engineer} | ||