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).
Extract from a report detailing a road test and feedback on low-pressure tyres.
| Identifier | ExFiles\Box 53\2\ Scan011 | |
| Date | 28th April 1923 guessed | |
| Extract Low Pressure Tyres Last Thursday I fitted these to the Cadillac, and ran down home to Woldingham, and during the week-end round Winchester etc till Tuesday, when I came back here having done some 700 miles running. I am delighted at the results on them - and as a noise reducer they are wonderful - eliminating the minor chassis noises - it is a revelation to change back to standard types. We came from Pall Mall to Fort Dunlop in 2hrs.50 min. with ease on crowded roads - just 40 m.p.h. for 112 miles. The driver finds that he may be a little slower on maximum speed (we were well above 60 lots of times) but he certainly can average higher speeds as bad roads don't count. (a) I can fit these wired on tyres with bare fingers and take off ditto. (b) I have no loose flange. (c) A.S.S.type of tyre quite waterproof. (d) No flap used or required. (e) 25 lbs. pressure ample for 5" or 135 load. (f) Weight of tyre and wheel is:- 4 lbs. more than 895 x 135 Wheel,Tyre and tube. Just same as 32 x 4½ .... " 4 lbs less than 33 x 5 ... " My Wheel can however be easily reduced to give same weight as 895 unit (g) The cost on a manufacturing basis should only be a matter of 4 or 5 shillings (at most) more than 895 x 135 unit. (h) I believe I will get 15000 miles as compared with 10000. (j) My tyre is very difficult to puncture. (k) I have a wonderful non-skid feature as the contact surface surface is long. (l) As to absorbtion well - on my Rover with 6" tyres, I get following results:- where resting on 1.9/16 dia.bar. | ||