Post War Racing 1919-1922:

Armistice was signed on 11 November 1918 ending the Great War; soon after in 1919, the first postwar Indianapolis 500 was held; postwar conditions in France were however less amenable and the first Grand Prix was not staged until 1921. In 1920 Sunbeam merged with Talbot and Daracq to form the STD group headed by Louis Coatalen as a managing director.

During the war in 1916 Sunbeam designed a 4.9lt engine in the Ernest Henry manner which preformed well in that years Indianapolis 500; J Christiaens finishing 4th; this engine type was fitted in 1919 in two shorter 1914 Sunbeam T.T. chassis and entered for Jean Chassagne and Dario Resta for the 1919 Indianapolis 500. The cars were shipped to the USA but were not submitted for scrutineering and were withdrawn for unknown reason. Jean Chassagne was consequently recruited by the newly formed Ballot Racing Team to drive one of their newly designed Ernest Henry straight eight 4.9lt cars; accident on the 63^rd lap due to steering problem resulted in what became Chassagne’s most serious accident in his entire career but despite having ejected some 150 yards from his car he was largely unhurt. Chassagne remind with the Ballot team and in 1921 became their top driver

A year later, in the 1920 Indianapolis 500 capacity limit was reduced to 183 cu (3-litre). The design of the Ballot entry was similar to the year before but scaled down to 3-litre ; Jean Chassagne was running in the first five places throughout the race but damaged steering dropped him to 7^th place winning $1,900. Back in Brooklands in the larger 4.9lt Ballot and with riding mechanic Robert Laly who was to become a life long friend, Chassagne made the fastest BARC lap of the year and finished second in the three handicap races. In the Gaillon Hillclimb, he made 22.6sec at 99mph.

Back in Indianapolis in 1921 with a private entry Peugeot 4cyl, Chassagne lost his bonnet and was forced by regulations to retire.

The long awaited French Grand Prix took place at Le Mans, on a circuit that was to become known as the Le Mans ‘24 hours Endurance’; Chassagne on the 3-litre Ballot thrilled the crowds with a neck to neck duel with Jimmy Murphy on his Dusenberg; on lap 17 Chassagne was leading but he was forced to retire with punctured petrol tank.

Chassagne had his break in the 1921 Italian Grand Prix with the Ballot where he came second and the Gaillon Hillclimb where he made 3^rd fastest time of the day. In November 1921 Chassagne, married the half English, half French Emma ; over the years, Emma escorted her husband on some racing events and they remained married until Chasssagne passed away in 1947.

1922 was a successful and busy year for Jean Chassagne with STD and at 41 years of age, his greatest victory in the Isle of Man Tourist Trophy. The year started with a win at Brooklands Easter Meeting with the now legendry aero engined Sunbeam 350hp which proceeded to break numerous Speed Records including the first car to set a new World Speed Record over the magic 150mph mark.

In June 22 after 5:24:50hr in what he famously described as “a nightmare in sea of mud” Chassagne won the first postwar Tourist Trophy and the last motorcar Tourist Trophy to be run on the Isle of Man with Sunbeam III a 1921 Sunbeam Grand Prix straight eight 3-litre modified for the event; Chassagne ordinarily a measured and meticulous driver was fazed by the atrocious weather conditions on the island that day but it remained “one of the greatest victories of his career”. Chassagne was entered in several voiturette racing for STD with the invincible 1921 1.5lt Talbot Darracqs, in effect a half sized engine of Chassagne’s winning Tourist Trophy car, but none gained him success.

Responding to the French Grand Prix formula change to 2-litre limit Coatalen engaged Ernest Henry who with the ‘Les Charlatans’ before the war was responsible for the development of the successful game changing dohc four valve per cylinder design Peugeot engines and postwar their offshoot the Ballot engines to design the new 1922 Sunbeam Grand Prix for that year’s event to be held at Strasbourg. Jean Chassagne knew Henry for many years and he acted as liaison between Henry in STD Surenes near Paris and the STD Wolverhampton Experimental Department, ultimately testing the prototype car in Brooklands and helping to develop the Sunbeam Grand Prix team entry. In the event, Chassagne drove Sunbeam I but the three cars retired after being the second fastest behind the winning Fiats. The cars were entered at the subsequent Grand Premio d’Italia Monza but did not appear. Instead, Sunbeam competed in the 1922 November 19 Coppa Florio in Sicily where Chassagne after holing the oil tank of his dreadnought grey 4.9lt 1922 Tourist Trophy Sunbeam with a stone on the rough Madonia Mountains track, and having replenished with olive oil locally purchased, finished forth but was unplaced.