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).
Test results for Englebert tyres, detailing mileage until failure on a 40/50 HP car.
| Identifier | ExFiles\Box 157\4\ scan0032 | |
| Date | 10th March 1922 | |
| ENGLEBERT TYRES. 10.3.22. Tests carried out on a 40/50 HP. R-R Car. Average weight - 47 cwts. Tyre pressure - 65 lbs. No.616152 (No.2) Miles on off-side rear -- 1760 " " near-side " -- 2000 ----- 3760 Cover and tube burst. No.614566 (No.5) Miles on off-side rear -- 1026 " " near-side " -- 1000 ----- 2026 Cover and tube burst. No.616096 (No.1) Miles on off-side front -- 2000 " " near-side " -- 2620 ----- 4620 Cover and tube burst. No.616272 (No.3) Miles on off-side front -- 2890 " " near-side " -- 2000 ----- 4890 Cover and tube burst. ------------------- | ||