Bentley reliability

The vintage Bentley was not only a fast car, it was commendably reliable. But this blend of all that was best in pre-war motor-racing technique, with an engine based on the victorious multi-valve twin-cam Peugeots and single overhead-camshaft Mercedes, needed to be publicised, introduced as it was during the slump-period that quickly followed the 1918 Armistice. How to achieve such promotion must have lain heavily on WO Bentley’s shoulders, along with the many other worries entailed in producing a new, expensive sports car.

It is good to know that he turned to racing and record-breaking to elevate his three-litre Bentley into the public eye. Rather unexpectedly, the first serious race in which a Bentley appeared was the 1922 Indianapolis 500. Unexpected, because the output from Cricklewood at the time would hardly have met any American sales that might have resulted from the cost of shipping a car across the Atlantic. To that point, only the Coatalen Sunbeam had ventured from these shores to tackle the uncertain gamble that was Indy. Perhaps the idea had originated in the mind of Douglas Hawkes, that versatile driver who got good results with anything from a 90 mph Morgan three-wheeler to the venerable 15-litre GP Lorraine Dietrich and most things in-between. It may be that he had negotiated some dollars towards the cost of driving the car at so distant a venue.

It worked out alright, the Bentley finishing the race at 74.95mph, albeit in last place. But WO’s next race entry was much easier to comprehend. He put a team of three Bentleys in for the 1922 loM TT. They could not be expected to win against pure racers such as the straight-eight twin-cam Sunbeams or Ricardo-Vauxhalls, but they could demonstrate speed with reliability. This they did, taking the team prize with second, fourth and fifth places. Like the Indy car, all had flat-fronted radiators. Maybe the classic design was regarded as scarce at the time, and was reserved for production chassis?

The TT was a useful exercise, but one thing I cannot fathom is an advertising panel issued by the Bentley Company after the race. It read: “The Tourist Trophy Team Prize won by the Bentley Team as follows: FC Clement second, WO Bentley fourth, WD Hawkes fifth. These results were secured with standard cars, the only modifications being high compression pistons. The standard Bentley was second by four seconds only. Its competitors were all special racing cars. The Bentley was only 0.64 mph slower than the fastest lap of the whole race.” The italics are mine. After the event the results showed that Chassagne’s Sunbeam had won in 5h 24m 50s, at 55.78 mph. Segrave’s Sunbeam had lapped in 39m 15s (57.7 mph).

Clement’s Bentley was second in 5h 28m 59.6s, WO’s fourth in 5h 43m 51 .2s and Hawkes’s fifth in 6h 28m 41s. WO set fastest Bentley lap, in 39m 43.6s. I cannot understand this claim by Bentley; can anyone explain it?

Be that as it may, in 1923 John Duff took his own Bentley to Le Mans, with Clement as co-driver. Although hampered by having rear brakes only and losing two-and-a-half hours when a stone punctured the petrol tank, they finished fourth, tying with a Belgian Excelsior and a French Bignan. WO had regarded this as 24 hours of folly, but capitulated at the last moment and, accompanied by his sales manager, travelled to the race by train. The following year, again with his own car, but with some works help, Duff won outright, and Le Mans was to become the best demonstration of Bentley’s speed with reliability. The firm’s achievements were thus: 1924 -1290 miles at 53.58 mph; 1927 – 1472 miles at 62.35 mph; 1928 – 1658 miles at 69.10 mph; 1929 – 1767 miles at 73.62 mph; 1930 – 1821 miles at 77.87 mph . . . after which the Bentley Company went into liquidation. But it had been a great record, earning valuable prestige for Great Britain.

However, we are leaping ahead of ourselves.

Duff had taken his three-litre Bentley to Brooklands in 1922 and had set a fine Double-Twelve Hour record of 89.7 mph. He drove unaided, out of his seat for just over 15 minutes on the second day. The car was in race-trim, with an extra tank for the Pratts petrol/benzole and an auxiliary tank for the Castrol oil, but it was virtually standard, with a non-streamlined four seater body. The only trouble was a loose screw that dropped into the choke-tube in the Claudel Hobson carburettor on the first day. Five Pirelli tyres were replaced as a precaution, and one burst. Wolseley’s record was handsomely beaten . . .

By 1925, his records having been broken, Duff went to Montlhery with the 1925 three-litre Bentley he had driven at Le Mans that year, to which had been fitted a Weymann leather-covered body with panels beside the cockpit which, raised, faired it in. The compression ratio was raised as was the axle ratio and different carburation adopted. With Dr JD Benjafield as his partner, Duff set out to attack the Renault 45’s 24-hour record. They encountered heavy rain and were delayed when number three exhaust pipe broke, two stops being needed to secure it, but Renault’s 1000-mile record was broken, at 97.7 mph, before the bottom bevel of the timing gear broke and the run came to an end. Repairs were put in hand and, with Woolf Barnato as his second driver, Duff was off again, 11 days later. This time the Bentley was successful, the 24-hour figure raised to 95.02 mph for the 2281 miles. This time fog was the hazard, yet lap times varied by less than one-fifth of a second over several circuits of the banked Paris track. Dunlop tyres were used, some already worn, and only four were changed. Pit stops were made every three hours and the first tyre swap wasn’t made until the ninth hour.

In 1926 WO thought that to take the world’s 24-hour record at over 100 mph would do Bentley Motors a power of good. A plywood and fabric-bodied long-tailed single-seater on a 9 ft three-litre chassis was prepared and Clement, Barnato, Kensington-Moir and Dr Benjafield were appointed to drive it at Montlhery for three-hour spells, attended by the works mechanics, with the object of wiping-out the Renault records. On the first attempt, with WO watching, the plugs gave out after three hours. After 16h 21m a valve spring broke and caused a valve to break. However, 13 Class D records had been secured, including a new 12-hour figure at 100.96 mph.

Another engine was installed and Clement, Duller and Barnato tried again later in the year, a Morris Cowley Chummy (as slave-car) and WO’s 6 1/2-litre Bentley going to Paris with them. Heavy rain was experienced and after 16 1/2 hours the car ran off the track while mechanic Walter Hassan was driving it in the absence of the regulars, after Duller had spun the Bentley and hurt himself. Bentley never did do 100 mph for 24 hours, but after this Le Mans offered adequate proof of their pace and durability. However, one should not overlook the Hon Mrs Victor Bruce’s 24-hour record with a Le Mans-type four-seater 4 1/2-litre Bentley, accomplished solo at 86.57 mph in 1929. Equally, there was the 24-hour Class C record, established at 91.05 mph in 1930 with a similar Bentley driven by Dudley Frey and Field, and later improved to 93.42 by Froy and Raphael in 1931.

In those later times the Le Mans victories were sufficient, however, to proclaim the Bentley’s toughness and justify the company’s five-year guarantee, surpassed only, I think, by the six-year warranty of the present-day Proton.