Inside the Museum: The Too-Late Twin

In Episode 8 of Inside the Museum with Classic Bike Man, John Oakes takes a closer look at one of the National Motorcycle Museum’s most intriguing racing machines with Museum Director James Hewing – the 1975-1976 750cc NVT Cosworth Challenge P86.

Known as the “Too-Late Twin”, the Cosworth-powered machine can be found in Hall 5, alongside an impressive line-up of racing motorcycles. At first glance, it certainly looks the part. With its striking design and Cosworth-developed engine, this was a motorcycle that appeared to have all the ingredients for success.

But the story turned out rather differently.

A Formula One connection

By the early 1970s, Norton’s Commando had proved itself a hugely successful racing machine, particularly in Formula 750. But its basic design was beginning to show its age, and Norton needed something new to take on increasingly powerful competition.

In 1972, NVT chief executive Dennis Poore approached Cosworth Engineering, the legendary British engine specialists whose 3-litre V8 had become a dominant force in Formula One.

The idea was ambitious: take the expertise behind Cosworth’s Formula One engines and create a 750cc two-cylinder engine suitable for Formula 750 racing – while potentially providing the basis for a new generation of road motorcycles.

The resulting engine was a highly sophisticated liquid-cooled, double overhead camshaft parallel twin, with four valves per cylinder and a six-speed gearbox.

On paper, it had enormous potential.

In reality, it took around three years to reach the track.

The right idea, at the wrong time

By the time the Cosworth-powered Challenge was ready to race in 1975, the landscape had changed dramatically.

John Player had withdrawn its sponsorship from Norton at the end of 1974, while NVT – created through the amalgamation of Norton, Triumph and BSA – was facing serious financial difficulties.

The Challenge made its racing debut at the 1975 Brands Hatch Race of the South, with works rider Dave Croxford involved in a first-lap pile-up. Two further outings followed in 1976, but the project never achieved the results that had been hoped for.

The problems were not simply down to bad luck. The engine was heavy, the gearbox proved troublesome and the motorcycle’s handling was compromised by severe engine braking and a high centre of gravity.

As James explains in the episode, the bike looked fantastic – but riding it was another matter.

“The engine sounds amazing…”

James has actually ridden the NVT Cosworth, taking the machine to an event in France.

And there is one thing that immediately stands out.

The sound.

With its Cosworth-developed twin-cylinder engine, the Challenge sounds unlike almost anything else in the Museum’s racing collection – more reminiscent of a Formula One engine than a traditional Norton.

But according to James, that is where some of the fun ends.

The bike is heavy, difficult to turn and not particularly effective under braking. Its weight is carried high, making its centre of gravity a particular challenge.

Even starting it is an experience. The engine is a stressed member of the chassis, with the swinging arm pivoting through the rear of the gearbox, and getting the engine running is notoriously difficult.

It certainly lives up to its name as a “Challenge”.

A glimpse of what might have been

For all its shortcomings, the NVT Cosworth remains one of James’ favourite racing motorcycles in the Museum.

It is also a fascinating example of the challenges facing the British motorcycle industry during the 1970s.

Norton, Triumph and BSA were attempting to compete against increasingly sophisticated international competition while dealing with limited funding and major industrial and financial difficulties. The Cosworth Challenge demonstrates both the ambition and the ingenuity of that period – taking expertise from Formula One, developing an entirely new engine and attempting to create a motorcycle capable of carrying the Norton name into the future.

Ultimately, it came too late.

But that doesn’t make it any less important.

As John and James discuss, it is easy to look back with hindsight and focus on the bike’s failures. But innovation depends on experimentation, and success cannot happen without some projects falling short.

The NVT Cosworth is part of that story.

There are believed to be only around three examples of the Challenge remaining, and the National Motorcycle Museum’s example is currently believed to be the only one still running. The Museum has also benefited from the knowledge and advice of Norman White, a hugely respected figure in Norton and NVT racing circles, who has helped keep the machine running.

And James isn’t finished with it yet. There are plans to potentially take the Cosworth Challenge back onto the track at Goodwood in 2027.

For now, you can find the “Too-Late Twin” in Hall 5, surrounded by some of the greatest racing motorcycles in the collection.

Watch Episode 8 of Inside the Museum with Classic Bike Man below as John Oakes and James Hewing take a closer look at one of the most fascinating – and frustrating – racing motorcycles in the National Motorcycle Museum.