AT LUNCH WITH...
He used ram air before the Japanese, had traction control in 1995 and turned a rotary police bike into a GP machine. We meet one of Britain’s most innovative motorcycle engineers
Brian Crighton, Norton rotary designer and great British inventor
When Norton rotary maestro Brian Crighton was 17, he wanted to tune his 50cc Honda C110 (a 1960s version of the Cub) to tease out a few more mph. No surprise there, it’s what we all wanted at that age (amongst other things). But what Brian did next set him apart from all the other speed-crazy teenagers of the era, and explains a lot about how he managed to create Norton race bikes that won three British championships, had huge TT success and even got a point in a 500cc GP.
First, he read everything he could about four-stroke tuning. But there wasn’t enough detail in the books to let him understand how the gases flowed through the ports
‘THE INTAKE WAS DRAWING IN COLD AIR, WHILE THE EXHAUST WAS CUNNINGLY DESIGNED TO PULL COOLING AIR THROUGH THE ENGINE USING THE VENTURI EFFECT’
and around the valves, which meant he didn’t know exactly how to shape them. So he dismantled his C110 engine, plumbed a hosepipe onto the inlet port and turned on the tap while working the valves. “Obviously, I got soaked,” he says, chuckling as we eat fish and chips at his local. “But if I wore goggles I could see how the water flowed and my theory was that if there was any turbulence you’d get the air in the water. It worked, and I played about with different shapes of ports to smooth out the flow. The water grips the surfaces just like air does, so although it’s a different medium, I learnt an awful lot from those experiments.”
With his now considerably faster C110, the next step was to race it. “I didn’t win, but I was mid-field – not bad on a road bike. Eventually I was able to afford a CR110, Honda’s 50cc race bike – eight-speed gearbox and four-valve head. By then the two-strokes were all winning the races, but I thought: ‘I’m sure I can make this go better.’
“So, I used my hosepipe system and then did a lot of porting, changed the cams and put electronic ignition on it. It used to rev to 17,000rpm and I even had ram air on it. I was 50cc British Champion on it in 1973, ’74 and ’76 – I missed it by one point in ’75. I beat the Kreidler two-strokes, which wasn’t bad.”
Of course there’s little in common between a 50cc four-stroke and the Wankel engines that Brian later became famous for, but his attitude to engineering was consistent. “I’m one of these people that, if I want to understand things, I’ve got to fully understand it and I’ve really got to go into it deep. With my CR110 I’d be going around people in the paddock saying: ‘Do you know what your valve timing is?’ and they wouldn’t have a clue. And I thought: ‘Why don’t they know? They should know that.’ They weren’t interested, but I always wanted to know that sort of thing.”
Clearly a handy racer as well as a highly inquisitive tuner, Brian tried racing bigger bikes, but struggled.
“I had a 500-4 that I’d worked on, which was quick. But with those big bikes you had to drift them a bit and I couldn’t do it, so I stuck with the 50s and 125s and got people like Dave Hickman [TT and BSB star Pete Hickman’s dad] to ride the bigger ones. He actually beat the works Suzukis on my 500-4.”
By then Brian’s links with Honda were more than just through racing. In his early twenties he ran a Honda dealership north of Birmingham, but it did not end well, and precipitated not only his move to Norton, but a deep distrust in Honda. “I did really well with the dealership,” he says. “But I didn’t enjoy the paperwork, so I got an accountant and he stole so much money from the business that we had to close in 1983. He got put in prison for nine months, but I lost my shop and Honda didn’t help, so my wife, kids and I got kicked out of our house, too. I wasn’t too chuffed with Honda. That’s one of the reasons why I wanted to beat them so much when I was doing the Nortons later on.”
Then came a stroke of luck. Ted Shaw – a mate of Brian’s who worked in Norton’s service department – let Brian have a go on a prototype twin-rotor Norton. “I thought it was fantastic – very quick and smooth. I said to Ted: ‘Bloody hell, you’ve got to get me a job there’.” Fortunately there was a job going and Brian ended up servicing the rotary police bikes. “That was great, because I had to test them and I would blast around everywhere looking like a policeman.”
At this stage the rotaries were still air-cooled, which meant they ran hot and often cracked around the spark plug. So Norton moved to water cooling, which got Brian thinking. “They worked well, and because I used to race, I thought: ‘This would make a fantastic race bike.’ At the time they were doing about 85bhp, and I knew I could get more power out of it than that. I kept saying to [Norton boss] Dennis Austin: ‘I’m sure I can get 120bhp out of one of these engines,’ but he wasn’t interested.”
What Brian needed was deeds not words. “There was a bike that had been lying in the corner for ages. I said to Dennis, ‘if you let me have this old police bike, I’ll work on it after hours. Anything that needs buying, I’ll buy myself – it won’t cost you anything.’ He agreed so I took the engine and did some modifications to the porting.”
Brian’s being modest here – he did considerably more than just a bit of porting. In fact, he changed the fundamental architecture of the engine. At the time, Norton’s engines drew air through the motor itself to cool the rotors before it went into the intakes, but that limited the power – it was like having a blocked air filter. “What I thought I’d do was have the engine draw air through the middle, and have a couple of fins facing forward into the wind to cool the engine.” This meant the intake was drawing in cold air, while he cunningly designed the exhaust to pull cooling air through the engine using the Venturi effect.
“The very first dyno test run I did one night – and I still can’t quite believe it – made 120bhp. Of course, I said to Dennis: ‘Look, I told you I could do this! Can I do a race bike?’ But, he still wasn’t interested – despite 120bhp without even trying!”
Eventually, after much persuasion, Dennis Austin gave in to Brian’s Brummy charms and allowed him to build a racer from what was left of the old police bike. "I cut all the back end off and put tubes in instead of the pressed steel and went to MIRA,” says Brian. “Bob Rowley was the test rider, and he did 170mph. This was in 1986, so that was quite quick for a 588cc bike. I thought they were bound to let me do a race bike after that, but still they weren’t interested. I got really pissed off and resigned – I was chief engineer by then, so it was a big decision.”
It wasn’t long before Norton realised they’d lost one
of the most innovative engineers they’d ever had and asked Brian to come back. He agreed, but with one proviso. You’ve guessed it: Norton had to let him build a racer. “It’s difficult to know where to start when you’re building a race bike from absolute scratch. The top bike at the time was the RG500, so we used its geometry and got Spondon Engineering to build an aluminium chassis. We turned up at Darley Moor and I think we came about third. But it wasn’t properly finished – it hadn’t even got a fairing bottom and it ran wide everywhere because it’s got so much torque compared to an RG.
“We went through a few iterations of different frames and eventually got there. By now the management was getting a bit interested.” Not interested enough to actually pay Brian to do it, mind – he was doing the race work at night and looking after the police bikes during the day.
One of the problem areas for the race bike was the gearbox, which kept breaking. “The trouble was it was based on the Triumph Trident gearbox. When Triumph closed, Dennis Poore somehow ended up with hundreds of Triumph gear clusters which Norton used in the earlier rotaries. They were alright as a road gearbox, and even in race practice. We could practice all day long without any problem – but as soon as you get in a race with everybody round you, you can’t hear what your engine is doing and you break the gearbox. Bob Rowley, who was by then one of the chief blokes at Norton, was really enthusiastic about the project, and helped us out a lot – but it was funny, as he was designing a new gearbox, I’d be developing the engine and getting more power. So I’d poke my head around the door and say: ‘Bob, I’ve got 142 now,’ and he’d have to keep beefing up his design.”
Despite the race project gaining momentum within Norton, the size of the company meant that funds were still tight. The team had a few sponsors who gave them oil, tyres, etc, but to achieve the bike’s potential, Brian needed some major cash. Along with then boss Sam Burns, he arranged talks with cigarette brand John Player Special (JPS) at Brands Hatch, where the team were racing that weekend. Coincidentally, he’d also persuaded Steve Spray to have a go on the bike, in place of usual rider Simon Buckmaster.
“Steve had never ridden it before, but he flipping won both races – the Powerbike International and the F1. The crowd went mad because a British bike with a union jack on it had won. The JPS people saw the enthusiasm and gave me £1 million for a three-year contract. That was a lot of money in 1988. And the next year we won the British F1 championship with Steve Spray.”
But with success came pressure, and Norton and JPS decided Brian had too much on his plate, what with running the race team and developing the bike. They brought in Barry Symmons as team manager, but the two clashed. “We just didn’t get on and I got really fed up with it, so I left,” says Brian, with the look of a man not overly keen to chat about a tricky period in his career.
He didn’t spend long twiddling his thumbs, though. Australian businessman Chris Oldfield had heard about the rotary and asked Brian to build him two race bikes. “These were the Rotons, which we managed to get accepted by the FIM to run in the 500 Grand Prix class – which was a bit weird because it was 588cc.
“Anyway, I built the first Roton at home in the dining room [with full support from his wife Doreen] and got Steve Spray to ride, but unfortunately you could see that he’d lost his confidence [after a disastrous move from Dunlop to Michelin the previous year]. But he came 15th in the Australian GP and got a world championship point – not bad for a bike I’d built at home. After that we got a rider called Grant Hodson, who ended up lapping 1.5sec faster than Steve, so we could have done better.”
After financial shenanigans left Brian inheriting the two bikes in lieu of pay, they became the Duckhams Nortons ridden by Ian Simpson and Phil Borley. Simpson won the
‘STEVE HAD NEVER RIDDEN IT BEFORE, BUT WENT AND FLIPPING WON BOTH RACES’