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).
The effects of rim width on vehicle handling, comfort, and tire performance.
| Identifier | ExFiles\Box 156\3\ scan0247 | |
| Date | 25th October 1940 guessed | |
| V.{VIENNA} CROSS-WIND HANDLING. The effect of the increased stability is more evident in cross-wind handling than in cornering power. VI. STEERING AND PARKING EFFORT. Slow speed steering and parking effort is slightly increased with wide rims. This is due to the reduced air pressure used with the wider rims. VII. TRACTION AND SIDE SKID. There is not much evidence on this subject, but such experience as we do have, indicates that the skid resistance is improved with wider rims due to the increased stability of the tires. VIII. RIDING COMFORT, HARSHNESS AND THUMP ON EXPANSION JOINTS ETC. Riding comfort will always be essentially a factor that must be decided by car manufacturers. Our experience indicates that a pressure reduction of from 2 lbs. to 4 lb. depending upon the car, is required to produce the equivalent riding comfort for the maximum change in rim width. The same difference in pressure is required to produce an equivalent degree of harshness and thump over expansion joints. IX. TIRE HUM AND SQUEAL. Tire hum on straight roads and squeal on turns was generally unaffected by rim width. | ||