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).
Impact of Dunlop's new inner tube joint position on wheel balancing schemes.
| Identifier | ExFiles\Box 4\3\ 03-page66 | |
| Date | 25th November 1926 | |
| Hs{Lord Ernest Hives - Chair} X401 BY16/H.{Arthur M. Hanbury - Head Complaints} 25.11.26. NOV 26 1926 wd.{Mr Wood/Mr Whitehead} C. Hs.{Lord Ernest Hives - Chair} WIRE WHEELS WITH WELL BASE RIMS. RECEIVED The Dunlop Company have changed the position of their joint in the inner tube relative to the valve. Our balancing scheme with a permanent plate rivetted on opposite the valve was based upon the fact that the joint in the inner tube fell on the same side of the centre line of the wheel as the valve itself, and comparatively near to it, with the result that the combined out-of-balance of valve and joint acted together, and by rivetting a permanent balance weight on the opposite side of the wheel, we approximately balance this combination. The Dunlop Company are now supplying, (to the Experimental Dept. at least, whether this is actually standard or not I cannot say,) inner tubes with the joint opposite the valve. The joint in the tube is by far the heaviest factor, and the result is that our balance weight as fitted by the Dunlop Company, if these tubes are used, will fall on the same side of the wheel as the joint of the inner tube, making it impossible for us to balance this combination by our existing scheme. One does not feel that there is very much to be gained, so far as we are concerned, by the proposal to make the joint on the inner tube fall diametrically opposite to the valve, particularly as we are committed to a fair number of wheels on the 20 HP. chassis at least, which were balanced to suit the original scheme referred to in my first paragraph. In my opinion, since we are already committed to one proposal, it seems to me a doubtful advantage which is under consideration at the moment, as it will unquestionably result in confusion later, if and when inner tubes of the new scheme are fitted to wheels which have been balanced with the old scheme. This matter is one which should be taken up with the Dunlop Company at once, to find out:- a/- have they committed themselves definitely on production to the proposed new scheme. b/- if not, can the scheme be wiped out. Its advantages are problematical; its disadvantages are very real. Contd. | ||