on another BSA Rocket 3. John Cooper rode a BSA Rocket 3 to an upset victory over 500 cc world champion Giacomo Agostini in the 1971 Race of the Year at Mallory Park. Cooper finished three-fifths of a second ahead of Agostini's MV Agusta. The best-known bike was a production-class Trident prepared by a team led by Les Williams called Slippery Sam, a roadster prepared for production-class road racing to controlled specifications using selected adaptations only, available from the factory as part-numbered inventory. Williams' team won consecutive 750 cc production races at the Isle of Man TT for the five years between 1971 and 1975, and in the new F750 event for race-specification machines, Triumph and BSA machines with Rob North frames placed first and second. Bert Hopwood recommended a production version of the racing triple, producing at 8,250 rpm, but his suggestion was not adopted. Further racing development was done in Duarte, California under racing manager Dan Macias. Tom Mellor set four world speed records at the Bonneville Salt Flats in September 2008 with a 1969 Triumph Trident T150. End of production Financial and management problems at BSA and the disintegration of the British motorcycle industry during the early 1970s led to a government-sponsored merger, "NVT", in July 1973 with Norton. Although Norton was very much smaller than BSA-Triumph, and it had only one product, the ageing pre-unit Commando, nevertheless control of NVT was given to Dennis Poore, the boss of Norton. Poore was much more "in tune" with motorbikes than were the BSA management, but Poore's business plan proved to be an asset-strip of BSA for Manganese-Bronze, rather than a consolidation of the remnants of the UK motorcycle industry. NVT's restructuring plans triggered a strike at Triumph's Meriden factory in September 1974. Production of the Trident was eventually transferred to BSA's Small Heath factory in March 1974, but the lengthy labour dispute disrupted production, and very few Small Heath Tridents came into being. The last machine off the assembly line at Small Heath, a police-specification Triumph Trident for Saudi Arabia, was produced on 18 December 1975. Later use of Trident and Rocket names After Triumph at Meriden collapsed, a new firm, Triumph Motorcycles Ltd, was established at Hinckley. The new firm manufactured from 1990 a new range of motorcycles with a modular engine design. Some of these bikes were called "Triumph Tridents"; and much later a "Triumph Rocket