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).
Bump test conducted on a 20 HP 'G' series chassis.
| Identifier | WestWitteringFiles\N\July1925-September1925\ Scan23 | |
| Date | 1st July 1925 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}/LS/LG3. 7.25. C BUMP TEST OF 20 HP. 'G' SERIES CHASSIS. Bumping front axle - Drum revs. 105. 2" lift cams, one on each drum and set at 180° apart. Load on front of chassis = 600 lbs. approx. " " rear " " = 1000 " " FRAME. Frame and fittings to F.53520 including parts to suit wider track 56", and EAC. type anchorage of front springs. FRONT AXLE. Standard for 4-wheel brake chassis. STEERING COLUMN. 'B' type steering. SPRINGS. Front - Firths 650 lbs.(F.53336) & 700 lbs. (F.53337) 12 1/2% Rear - " 900 lbs. (F.53172.) BREAKAGES. excluding road springs. Steering. During 105 hrs. run, 1/4" bolts which fasten down steering tube to box sheared off four times and the flange broke round its lower half four times. The steering wheel being locked, the stress set up by pendulum lever is in a direction along line of column and taken by flange and bolts. Under ordinary conditions where steering wheel is not rigidly fixed contd :- | ||