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).
Log sheet detailing tyre performance, mileage, and condition over several test runs.
| Identifier | ExFiles\Box 45\1\ Scan223 | |
| Date | 21th May 1921 | |
| Date. | Tyres fitted. | Position on car. | Total miles. | Daily miles. | Route. | Remarks. | | | F.{Mr Friese} | R.{Sir Henry Royce} | 21.5.21 22.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4081 4081 | 4015 4081 | 269 | Blackpool and back. | No.4998 slightly cut in wall. Repaired and fitted. 203 miles. 23.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4106 4106 | 4040 4106 | 25 | Local test runs. | 24.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4137 4137 | 4071 4137 | 31 | ditto. | 25.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4173 4173 | 4107 4173 | 36 | ditto. | 26.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4209 4209 | 4143 4209 | 36 | ditto. | No.4998 - burst. This cover is very worn. Taken off. Total miles run 4107. 28.5.21 29.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4373 4373 | 4373 | 164 | Derbyshire. | Average speed 30 M.P.H. Give and take roads. 30.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4411 4411 | 4411 | 38 | Local | 31.5.21 | WGD.4088 WGD.4261 WGD.4998 WGD.4257 | O front N front O rear N rear | 4463 4463 | 4463 | 52 | Local | CONTD:- | ||