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).
Vibration issues and tests conducted on Mr. Worthy's car no. 2025.
| Identifier | ExFiles\Box 3\1\ 01-page082 | |
| Date | 8th February 1913 | |
| EXPERIMENTAL "A" DEPT. REPORT Work in progress week ending 8/2/13. _VIBRATION ON MR. WORTHY'S CAR NO. 2025._ Description of the Car. The engine is a standard one but is very powerful, the chassis has no frame struts and is fitted with 3 elliptic springs, it has a spring coupling. The body is an enclosed type similar to the grey one which was on 1731 at Le CanadelHenry Royce's French residence last year. The vibration complained of by Mr. Worthy is at 18 to 24 miles per hour, the worst part is at 18 to 20 m.p.h. It is a slow vibration & seems to agree with the explosions, it is effected by power with either very weak mixture or partially closed throttle, it can hardly be felt on the road. The affect of the vibration is the most objectionable part of it, it vibrates the body & causes a boom inside which seems to fill up ones ears and makes most people feel ill. It can also be felt on the floor boards. I agree that the car is not fit for trials in its present state. It is possible to feel the period and hear the boom when the car is stationary and the engine running light, it is at the same speed but nothing like as bad. Tests with engine being driven. We jacked up the rear wheels of 2025, backed another car up to it, jacked up that, also took the tyres off both & fitted on crossed belts so that we could drive either by the other. This is a most adaptable rig as you can get full power by using one as a brake and get any speed by exchanging gear. We found on this rig we could pick out a vibration at 560 to 640 revs. which is the speed complained of, also there was another at a higher speed 900 to 940 revs. this was not complained of but would be felt on the road when one knew what to look for. The vibrations can be felt all over the frame, body, tyres and engine, the most convenient place we found was to sit on the frame and feel the top of the cylinders. Inside the vibrations and booming can be felt and heard but they are nothing like so bad as with the power on. The following are various test which have been done with the engine being driven:- Test No. Condition. Result. 1 Standard Car throttle open. Periods from 560 to 640 revs, 900 to 940 revs, both distinct, the low one the worst, also slight period at 1100 to 1200 revs. over 1400 revs. the vibrations are there all the time slightly. (Handwritten on left margin): 181X | ||