1924 24 Hours of Le Mans

With tougher target distances, as well as hot weather, the cars had to be pushed harder and this year only 12 of the 41 starters completed the 24 hours.

[1] The 4-litre Chenard-Walcker of the 1923 winners René Léonard and André Lagache had the early lead, for the first three hours, until it caught fire on the Mulsanne Straight.

The delay meant its remaining laps would not be counted according to the new race-regulations, as the average speed would be below that achieved to reach their target distance.

The Bentley victory brought international acclaim and cemented the popularity of the race as a significant European event.

[2] After the success of their inaugural 24-hour event, the Automobile Club de l'Ouest (ACO) set about making further improvements.

Firstly, the race-timing was moved to the summer solstice in late June to make the best use of the extended daylight as well as the higher probability of better weather.

[1][3] The ACO also recognised that the Triennial Cup format was unworkable after an unexpectedly large number of cars had qualified from the year before.

Émile Coquille, co-organiser and representative of the sponsor Rudge-Whitworth was still keen on a multi-year format, so a compromise Biennial Cup was initiated instead.

[4][5][6] Specifications were tightened up on chassis features like windshields, running boards and seats to prevent abuse by manufacturers trying to save weight.

It became compulsory to carry one spare wheel on board, exhausts had to be aligned to not blow dust off the road, and cars had to have functioning headlights between designated hours of darkness (8.30pm to 4am).

A minimum of 20 laps had to be driven before a car could stop to replenish fuel, water or oil fluids, still done solely by the driver.

[9] After being initially sceptical the previous year, W. O. Bentley was now a firm convert, and offered to provide John Duff full factory support for a return to Le Mans.

[10] A new range of the La Lorraine-Dietrich B3-6 3.5-litre cars were unveiled at the end of 1923, including a Sport version deliberately built for racing.

The team had already done well, winning the first post-war Monte Carlo Rally and setting 24-hour endurance records on the new Montlhéry circuit.

It was founded in 1903 by former Panhard et Levassor engineer Baron Charles Petiet and had competed in the early inter-city races.

Arthur Duray had set land speed records before the war and finished second in the 1914 Indianapolis 500 behind René Thomas.

[17] Likewise Georges and René Pol, who made taxis and delivery vans, wanted to venture into the sports car field.

[23] At the end of the first lap, it was the 3-litre Bignans of de Marne and Ledure with Lagache's big 4-litre Chenard-Walcker between them setting the pace.

[23] Straight away, de Marne easily beat Clement's lap record from the previous year by 15 seconds.

The Bachmann's Chenard-Walcker caught fire while in the pits, the two Oméga-Six then retired as did the leading Bignans, suffering from overheating.

[1][24] Louis Chenard's only appearance at Le Mans also ended early when a stone through the radiator stopped it seven laps before the 20-lap replenishment point.

De Marguenat ran out of fuel after 18 laps, and the others (after being frantically told to slow down) only just made their first stop.

[13] So, without close pursuit, Lagache was able to set about building a sizeable lead, while lowering the lap record even further.

Then at 8pm as dusk fell, soon after Léonard took over the leading car, the big Chenard-Walcker caught fire going down the Mulsanne Straight.

[26] But at 3am de Courcelles slid off the road and bent his Lorraine's chassis delaying it as repairs were done, and slowing it for the rest of the race.

[5] The Bentley moved up when Bloch then had to stop to repair broken rear shock absorbers – the Lorraine's Hartford duralumin units not strong enough for the treatment on the rough roads.

[27] The 12CV Chenard-Walcker running 7th lost two laps when de Zúñiga burnt his hand doing engine repairs, but his co-driver Dauvergne could not be found to take over and had to be hailed over the loudspeakers.

[5] Although the Rapson tyres were still working well, at 2.30pm Bentley called their car in for a precautionary change of the rear wheels.

The long stop had, however, left the Bentley very close to losing the race as its final five laps (including pit-stop time) would be well below their prior race-average and therefore not be counted per the updated ACO regulations.

Best performances, winning the second interim leg of the Triennial Cup was the Verpault/Delabarre Brasier, ahead of the 2-litre Chenard-Walcker of Dauvergne/de Zúñiga and the Bentley.