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).
Requesting information on the rolling resistance of specific wheel sizes and co-efficients for different surfaces.
| Identifier | ExFiles\Box 158\1\ scan0213 | |
| Date | 21th September 1938 | |
| 1375 To Sr... from Da{Bernard Day - Chassis Design}/Ev.{Ivan Evernden - coachwork} c. to By.{R.W. Bailey - Chief Engineer} c. to Rm.{William Robotham - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions} ----------- Da{Bernard Day - Chassis Design}/Ev.{Ivan Evernden - coachwork}4/N.21.9.38. ----------- Re: Rolling Resistance. ----------- We are interested in the rolling resistance of wheels of the sizes 5.5 x 18, 6.500 x 17, 6.500 x 16 in particular. We would be very glad if you would give us information concerning the variation in the resistance to rolling with speed and inflation pressure. The other factor of interest is the co-efficient for varying road surfaces, and also for a road wheel dynamometer of a given drum diameter in cast iron. We need this information to enable us to separate the rolling resistance from the wind resistance, after measuring the total drag of a car at various speeds. Rm.{William Robotham - Chief Engineer} has suggested that we approach you with a view to your getting into touch with Michelin. Da{Bernard Day - Chassis Design}/Ev.{Ivan Evernden - coachwork} | ||