The ex-Pat Mahoney, Barry Sheene
1973 Seeley-Suzuki TR500 Monocoque Racing Motorcycle
Engine no. 10063

• Unique monocoque prototype
• Restored in the 1990s

By the late 1960s, stressed skin, or 'monocoque', chassis construction had established itself as the norm for Formula 1 cars, so it was hardly surprising that some enterprising designers sought to apply this technology to the construction of racing motorcycles. One such was Colin Seeley, who had already established himself as frame-maker par excellence to the racing community, supplying tubular frames for, initially, AMC singles before branching out to cater for other makes of engine. By 1972, Seeley was also involved in managing production of Brabham's Formula 2 and 3 cars at its factory in Surrey. Brabham understood monocoque technology, though they had been late to embrace it, while no-one knew more about racing motorcycles than Colin Seeley: the result was the machine offered here, which was built over the winter of 1972/73.

Designed by ex-AMC man Bob Cakebread, assisted by Les Apps, the Seeley monocoque chassis was made by Brabham's top F1 fabricator, Nick Goozée. Steel fabrications were used for the head stock and swinging-arm pivot, while the panels were aluminium-alloy, riveted together. The forks and swinging arm were off-the-shelf Seeley components, but the alloy wheels and plasma-sprayed aluminium brake discs were specially developed for the Monocoque. Power was supplied by a Suzuki TR500 racing engine.

Following its debut at the Motorcycle Mechanics-sponsored Racing Show in January, the completed Seeley-Suzuki Monocoque was tested at Brands Hatch in February prior to the start of the 1973 season; ridden by Barry Sheene and Pat Mahoney, it completed 37 trouble-free laps and received nothing but praise from both riders. Mahoney was Seeley's only official rider for 1973, campaigning the Monocoque in the '500' class and a conventional Seeley-Kawasaki triple in the '750' category. In a domestic season dominated by Barry Sheene on his tubular-framed Seeley-Suzukis, the best Mahoney could manage on the Monocoque was a brace of 2nd places, both at Brands Hatch (Easter meeting and the Hutchinson 100). Sheene rode the Monocoque only once, at Mallory Park on 4th March, but dropped out with engine trouble. With Colin Seeley's time fully occupied by his other commitments, this promising machine received next-to-no development, and at the end of 1973 it disappeared from view.

For the next 20-or-so years the Monocoque remained in storage, and by 1992 was back in Colin Seeley's custody, albeit with some components missing, including the engine. Colin Seeley then sold the Monocoque to collector Stewart Newton, who proceeded to restore this unique machine to its former glory, fitting the replacement TR500 motor supplied by Colin. The story of its resurrection was published in Classic Racer magazine (copy article on file) while the story of its birth is covered in the second part of Colin Seeley's fascinating autobiography, 'Colin Seeley ...and the rest' (Chapter 4).

Stewart Newton subsequently sold the Seeley-Suzuki Monocoque to current vendor Phil Morris, and it was while the machine was in Phil's care that it was tried again by the late Barry Sheene, who rode it at the Oliver's Mount 'Cock o' The North' meeting. The machine was last ridden - by ex-Suzuki works star, the late Frank Perris - on the Parade Lap at the Isle of Man TT in 2002. The fuel tank has been signed by both Frank Perris and Barry Sheene. Accompanying documentation is contained within a substantial history file (perusal recommended).

Under different circumstances and with greater development, the Seeley-Suzuki Monocoque would surely have achieved much more; it remains one of motorcycle racing's more fascinating 'might have beens'.