Question: What did the man who died 23 March 1981 ride in the 1967 Isle of Man Tourist Trophy

Context articles: Four Inch Course
2007 Isle of Man TT
William Watson (motoring pioneer)
1950 Isle of Man TT
1926 Isle of Man TT
1967 Isle of Man TT
1932 Isle of Man TT
1949 Isle of Man TT
1952 Isle of Man TT
Mike Hailwood

The Four-Inch Course was a road-racing circuit first used for the 1908 Tourist Trophy Race for cars, held on public roads closed for racing by an Act of Tynwald (the parliament of the Isle of Man).
 The name of the course derives from the regulations for the 1908 Tourist Trophy adopted by the Royal Automobile Club, which limited the competitors' engines to a cylinder-diameter of four inches.
 The Four-Inch Course was adopted by the Auto-Cycle Club for the 1911 Isle of Man TT Races.
 The Four-Inch Course was subsequently known as the Snaefell Mountain Course or Mountain Course when used for motor-cycle racing.
The 2007 Isle of Man Tourist Trophy was the Centenary event which ran between 26 May and 8 June 2007.
 The first event was held on Tuesday 28 May 1907 and was called the International Auto-Cycle Tourist Trophy run by the Auto-Cycle Club on the St. Johns Short
William Watson (6 November 1873 – 5 August 1961) was a Liverpool-born racing driver and motoring pioneer.
 A champion cyclist as a young man, he founded W Watson & Co, cycle and motorcar manufacturer, in 1901.
 He won the epic 1908 Isle of Man Tourist Trophy Race driving a Hutton-Napier named "Little Dorrit".
 He also raced in Berliet, Vauxhall and Essex cars.
 He expanded Watson & Co from Liverpool to Chester, Colwyn Bay, London, Birkenhead and Crewe, creating the largest car distributing organisation in the North of England, specialising in Morris and Rolls-Royce cars.
The 1950 Isle of Man Tourist Trophy festival was the second year the Isle of Man TT races were part of the Grand Prix World Championship.
Further changes occurred in the 1926 Isle of Man Tourist Trophy with the scrapping of the Side-Car TT and Ultra-Lightweight TT Races from the lack of entries.
 Most of the TT Course had now been tarmacked, including the Snaefell Mountain Section.
 Another change in 1926 was the ban on alcohol based fuels, forcing competitors to use road petrol.
 Despite these changes the prestige of the Isle of Man TT Races had encouraged the Italian motor-cycle manufacturers Bianchi, Garelli and Moto Guzzi to enter.
The 1967 Isle of Man Tourist Trophy was a motorcycle road racing event held at the 37-mile Snaefell Mountain course on the Isle of Man.
 Five races, in different engine-capacity classes of 50, 125, 250, 350 and the 500 cc Senior TT, were the second round of the FIM World Grand Prix motorcycling championship season (now known as MotoGP).
 Mike Hailwood, on the four-cylinder Honda RC181, duelled with Giacomo Agostini's MV Agusta 500 Three.
The 1932 Isle of Man Tourist Trophy race meeting was watched by Prince George, Duke of Kent the first royal visitor to the Isle of Man TT Races.
 The 1932 Junior TT Race was won by Stanley Woods riding a Norton at an average race speed of 77.16 mi/h from Wal Handley and Tyrell Smith riding for the Rudge factory.
 Again Rudge where beaten in the 1932 Lightweight TT Race by Leo H.Davenport riding a New Imperial motor-cycle at an average race speed of 70.48 mi/h .
 The 1932 Senior TT Race provided Stanley Woods with the "Norton Habit" and another Junior/Senior double win at an average race speed of 79.38 mi/h .
 The 1932 Senior TT Race was initially led on the first lap by Norton teammate Jimmie Simpson who set a new overall lap record of 27 minutes and 47 seconds at an average speed of 81.50 mi/h .
 Also on the first lap Wal Handley riding for Rudge crashed at the 11th Milestone sustaining a back injury and retired.
 The place on the TT Course where the incident occurred was renamed Handley's Corner.
The 1949 Isle of Man Tourist Trophy was the first round of the Grand Prix World Championship that was held in the Isle of Man.
The 1952 Isle of Man Tourist Trophy was the start of Bob McIntyre's association with the Isle of Man, when he came second in the Junior Clubman TT that year.
 Irishman Reg Armstrong won his first Senior TT event as well as coming in second in the Junior TT race on a Norton.
 Armstrong, as a Norton works rider, was back-up to Geoff Duke who came first in the Junior race.
Stanley Michael Bailey Hailwood, {'1': ", '2': ", '3': ", '4': "} , {'1': ", '2': ", '3': ", '4': "} (2 April 1940 – 23 March 1981) was a British Grand Prix motorcycle road racer.
 He is regarded by many as one of the greatest racers of all time.