NORVIL PRODUCTION RACER
All about the Norton PR – the ’70s Brit proddie racer for the road
Back in 1970, production racing was big news. Success in the many production races run in the UK sold bikes. It was as simple as that. So it was no wonder that Norton Villiers – hot on the heels of the 1968 launch of the Commando – wanted a piece of the action. By then, production-based racing had been the fastest-growing sector in road racing for a number of years and the introduction of a proddie class race at the TT was proof of its popularity. The Commando looked made for the job.
Certainly, tuning wizard Paul Dunstall thought so. Together with Norton Villiers, he developed tuning kits for the new model using parts homologated for production race use, while south London Norton dealer Gus Kuhn Motors built their own successful proddie racer based on the Commando, too. And the first production racer to be prepared by Norton Villiers themselves was put together for the 1969 season at the works experimental department in Woolwich.
The bike, built by Eric Goodfellow and John Mcclaren, featured a tank, seat and fairing from Kent-based REG mouldings and the engine tuning was based on the parts developed in collaboration with Paul Dunstall – which, crucially, had already earned homologation approval for production racing. Track testing by Peter Williams proved the potential of the bike and, when the experimental department moved to the Norton/ajs development department later in 1969, a new Norton Villiers performance shop was set up under Peter Inchley.
Adopting the branding ‘Norvil’ for its own tuning parts, the new department was to become the birthplace of Norton’s ready-to-race production racer. And, after a reasonably bright 1969 season in which the factory prototype racer finished a very close second to Malcolm Uphill’s Bonneville in the Production TT in the hands of Paul Smart, the first ‘production’ production racer – the Commando PR – debuted at the Racing and Sporting Motorcycle Show in February 1970.
Just 35 of the bikes were built in 1970 and specification varied slightly according to customers’ requirements. While racers could subsequently modify exhausts, engine tuning and suspension, the major components of the bike had to remain as supplied and homologated. Because of that, the PR’S catalogued specification was significantly different to the roadster models.
The engine featured high compression, 10.25:1 Hepolite Powermax pistons, a skimmed and ported head, and was selectively assembled in the performance shop. The carburettors had to remain at the stock 30mm bore to comply with production race rules and, though a few very early PRS featured Amal GP instruments, the majority were fitted with the easier-to-tune Concentrics. Special welded-up stubs replaced the stock castings. The gearbox featured close-ratio
internals – with a Quaife five-speed ’box as an option. And, because the rearset footrests meant the gearshift lever had to be reversed, the selector camplate was, too, to retain the up-for-first, racing shift pattern. A final, neat touch was a longer kickstart lever to provide a better swing for easier starting in races with a dead-engine start.
There were special tucked in, exhaust header pipes, which gave the Dominator-style silencers a racy tip up, and the front brake was a Peter Williams-designed Lockheed single disc (a Grimeca drum is fitted to our photographed machine) with a caliper mounting cast into the front of the right-hand fork slider. Modified damping in the forks improved their action. Naturally, full road-legal lighting was provided front and rear, while a glassfibre handlebar fairing and race seat were standard, with 16, 23 or 27-litre options available for the tank – also constructed in glassfibre. Finish was almost invariably a striking bright yellow and, before long, the Norvil racers had acquired their ‘Yellow Peril’ nickname.
The second year of production saw a few changes to specification. Most of them followed that year’s upgrades to Norton’s roadster range, including the use of a modified Commando Roadster oil tank, ‘peashooter’ silencers and larger, 32mm Concentric carbs – though GP carbs remained as an option. There was electronic ignition, too – using an early version of the Lucas Rita system, which was developed by Lucas with input from the Thruxton race shop. Power was boosted, with 3S profile cams and a little more work on porting. As a result, the Commando PR made around 10bhp more than the standard road bike range – good enough for a top speed of around 130mph. To put that into perspective, the works-prepared race bike ridden by Paul Smart in the 1969 Production TT was clocked at 138.5mph on a slightly downhill section of the course. It was good enough to make the Commando PR a competitive tool in production class racing for a number of seasons to come.
Although 105 complete bikes were built at the Thruxton race shop over two years, the Norvil catalogue listed all the parts used in their build separately, so the owner of a stock Commando could bring it up to PR spec if they were handy enough with the spanners. And, thanks to Norvil Motorcycles (norvilmotorcycle.co.uk) that’s still possible today, as they still produce all the parts required to convert any Commando into a street-legal production racer.
In fact, the bike illustrated here is a replica, built by owner Dave Bruce. “I came across a 1972 frame and had a spare 750 Commando engine kicking about, so I decided to build a proddie racer rep,” he says. “I got hold of an original Norton Villiers racing spares brochure, which listed everything used on the factory-built Commando PRS and just went from there.”
The result looks stunning – and pretty close to the original, aside from that 200mm Grimeca brake laced into an alloy rim. The wheel
was something Dave already had when he started the project, so he decided to use it, but Norvil can supply the parts needed to revert to the original specification disc if he ever feels the need.
Original, Thruxton-built Production Racers have become highly prized and collectable in the 40 years since they joined the official Norton line-up. It’s estimated that less than 30 were supplied through UK dealers, making a genuine proddie racer a rare beast indeed. They rarely come up for sale, but a 1970 model, with the optional five-speed gearbox and 27-litre tank sold for $29,000 at Mecum’s Las Vegas sale back in 2015. A standard Commando of the same vintage and in the same condition would probably have made $800010,000. If you fancy one, check everything thoroughly.
The idea of manufacturing a special model for what was supposed to be a production bike racing class might seem a little strange. Almost certainly, with the amount of work that went into each Commando PR, Norton weren’t making a fortune out of them, either. But the increased interest in production racing meant that potential road bike customers were taking ever more notice of what was winning the races when considering buying a new model. And, with a competitive, over-the-counter track weapon for the class, Norton were soon figuring in the results regularly. As a marketing tool, it’s likely that the Commando PR made a lot of sense. It also made for a great looking – and sounding – machine.
‘I CAME ACROSS A 1972 FRAME AND
HAD A SPARE 750 ENGINE, SO DECIDED
TO BUILD A PRODDIE RACER REP’