Rumblings, March 1941



More Mark V, or a Study in Average Speed

THE opportunity arose again, the other day to take out a Mark V 4¼-litre Bentley saloon, which was described very fully in last month’s issue. Certainly an opportunity not to be missed, and we made the most of it by logging some average speed figures. Interest was lent to the outward run because John Day, who wrote some time ago of the advantages which he considers the motor-cycle has over a car under war conditions, was covering the same route as the Mark V, mounted on his 500 c.c. o.h.c. Vincent-H.R.D. “Meteor.” A deliberate race would have been unwise and was not attempted, but the run did provide something of an answer to the oft-discussed question of whether a fast solo motor-cycle is faster than a car on a journey of reasonable duration. We started from Western Avenue, London end and concluded our logging when the previously-zeroed speedometer trip showed 100 miles, which it did after some eight miles of crawling legally and regally round Cheltenham’s fair streets. The time taken was nicely under two hours. Those of you who are starting to frown may like to know that every built-up area was properly negotiated by both vehicles, even to braking hard down to 30 m.p.h. before the restriction signs and not opening up again until the derestriction discs were definitely reached. Second gear was naturally made good use of for regaining speed, but otherwise overdrive was habitually employed and the Bentley cruised at 70-80 m.p.h. The H.R.D. had “greater” acceleration and got through traffic gaps better; we had more speed and kept warm. So far as we were concerned, the first half hour saw 26 miles put away, which included five minutes of High Wycombe’s notoriously long speed limit. After an hour’s running the Mark V had covered 49.5 miles, in spite of having quite a deal of heavy convoy-commercial traffic to pass, and icy going, calling for some restraint, down the hill before the “Lambert Arms”—also, High Wycombe had had to be endured for six minutes of this second half hour. The icy conditions, which had spelt disaster for several family saloons, persisted for the remainder of the run, and no attempt was made to cruise at the car’s absolute maximum, although along the Oxford By-Pass it exceeded and comfortably maintained over 90 m.p.h., equivalent to 3,700 r.p.m. in overdrive. Even on this fine stretch of road we were destined to be delayed, for army lorries were using the full width of the highway in which to turn and a convoy-pointsman had brought us to rest at the first roundabout. Nevertheless, the average accomplished during the third half hour was 61.2 m.p.h., and 1½ hours after leaving London we had gone West to the tune of over 80 miles; a little tyre scream on occasion and the air-flow round the body were about the only other contributions to the theme . . . . Very soon afterwards, after some slight slides had made us give up 10 m.p.h. of our possible cruising speed in deference to Jack Frost, we entered Cheltenham and the remaining eight miles needed to complete our self-imposed task we disposed of in negotiating some ludicrous roundabouts and seemingly nearly all the streets of that city, probably at an average of nearer 20 than 30 m.p.h. And so. some minutes within the time limit set, the 100 miles were up and we had the satisfaction of knowing that this much-praised new British high-performance car can easily score a “century” in under two hours, without breaking the law, without attracting any unwelcome attention and without especially favourable conditions. Incidentally, the water temperature read 82°C. immediately after the run and the fuel consumption appeared to be about 13¾ m.p.g. That would be about right, for the maker’s figures are 24 m.p.g. at a steady speed of 35 m.p.h., 20.3 at 50, 18 at 60 and 14.7 at 70, using better fuel than we get nowadays. The overall average was at over 51 m.p.h., we were halted at at least two sets of traffic lights and, of course, it was all most effortless and enjoyable, the remarkably light-action brakes giving a complete sense of security. Later that day we had several times to cruise at 90 m.p.h. again, because the young lady on my left complained that she disliked crawling, whenever the speedometer needle dropped to anything approaching 70 m.p.h.

Under the wintry road conditions that prevailed we were not surprised when Day ceased to appear in the mirror after we had slid about going down the hill towards the “Lambert Arms.” When really icy conditions were encountered later, we imagined he would retrace his tracks London-wards. We had gravely misjudged him, for as we came back through Cheltenham immediately after checking our times the H.R.D. came in sight. John had been off twice and had just picked the machine up and ridden on. As far as we could make out, he had entered Cheltenham about 8 minutes after we had, which is, perhaps, equal to a dead-heat under the circumstances. Certainly an extremely stout ride and one that gives plenty of food. for thought. The Vincent. is not by any manner of means a recent production, and it is in daily use for journeys of national importance, including Home Guard patrols. It has been abroad as far as Venice in happier times and has a big mileage to its credit. On this run it did, we believe 60 m.p.g. of “Pool.” Compare its first cost and running costs to those of the Bentley and you see clearly the motor-cyclist’s argument. Against that, most people, car and motor-cycle enthusiasts alike, have predicted that a motor-cycle would be considerably faster than a car on a run such as the one we undertook, when the question has been raised at odd times. So Bentley Motors Ltd. have the satisfaction of being able to say to such folk that they have a very fast average-speed car indeed in the Mark V should they want to, which we do not suppose for a moment they do. You may say you would not care to come off your mount as Day did on this occasion. That would be unfair, because far worse was happening to family cars and army vehicles on the skating-rink surface, and, anyway, after lunch in Northleach, Day cheerfully set out to ride home to Nottingham. And the day before he had ridden to Stevenage to get, a solo sprocket and stronger valve springs, although this gave very little more speed than the sidecar sprocket he had been using—a new back chain was wisely fitted, too, as a safety measure. Of course, if there had been no ice . . . . Anyway, it was all very interesting and proved the Mark V Bentley to have every bit as much performance as the earlier 4¼-litres, besides all the refinements detailed in last month’s road-test report. Figures for the “Corniche” Bentley, and for the big-twin Vincent-H.R.D. would be instructive, but they may never happen, at any rate until the war is won. Meantime, we are quite convinced that it is possible to motor 100 miles in under two hours on British roads as they exist to-day, without inconveniencing, far less endangering, man or beast. If only our politicians will show an intelligent appreciation of how cars like the Mark V Bentley can cope with our road conditions when unrestricted motoring is passible once again, we shall not mind what the Pedestrians’ Association thinks and says. Concluding these notes a week after the run, we still retain very vivid and endearing memories of perfect braking, a remarkably rapid synchro-mesh, right-hand gear-change, the car’s extreme silence, and acceleration which took you up to 70 m.p.h. out of built-up areas almost before you had thought of opening up. A quality car like the Mark V mingles its personality with the personality of the occupants, and the sense of satisfaction and uplift imparted lives long after the drive is concluded—a welcome tonic these troubled times.