Each spring the convivial atmosphere of the Goodwood Members’ Meeting is rent asunder by a sound unknown to most car-racing enthusiasts: the banshee wail of two-stroke Grand Prix bikes.
The grid for the Mike Hailwood Trophy is always dominated by Yamaha TZ250s and 350s, which should come as no surprise, because these machines ruled 250/350 GPs from the early 1970s to the early 1980s. In fact the bikes not only dominated, they also democratised the sport, allowing talented privateers to challenge for world titles on production-line race bikes.
No other racing motorcycle has sold in greater quantities than the TZ. The machines became the mainstay of racing for more than a decade, from Snetterton to Suzuka and from GPs to national events and club meets.
During 1973, the first year of the water-cooled TZ (which followed the air-cooled TD250s and 350s), all but three of the 47 riders who scored points in the 250 world championship rode TZs. Ten years later, about two-thirds of points scorers still rode the bikes. In little more than a decade, TZs won 18 world titles in the 250 and 350 categories.
The water-cooled parallel twins were ridiculously cheap, considering what they could achieve. In 1976 a TZ250C cost £1500, while the 350 cost an extra 50 quid. That’s roughly £10,000 now, which wouldn’t even buy a suspension set for a modern GP bike.
Although two-strokes are long gone from the world championship, the TZ has a link to modern-day MotoGP. One of the founding principles of Moto2 was to recreate the age of TZ racing, when a good rider could win without worrying about going bankrupt.
An important factor in the success of the TZ was that Yamaha made near-identical 250 and 350 versions, so riders could buy one of each and work their way around the national or international circuits, earning enough start and prize money from doing both classes. Race paddocks were full of the machines, with riders and mechanics working day and night to keep them running at their prime.
A whole industry grew up providing trick bits for TZ riders who wanted to get ahead: Bartol barrels from Austria, Hoeckle crankshafts from Germany and so on. And then there were the road-bike derivatives: the RD250LC and RD350LC, which launched the careers of top racers like Mick Doohan and Niall Mackenzie.
Many TZ riders had the time of their lives: driving around Europe, scraping a living doing what they loved. GP winner Mick Grant remembers his TZ privateer years fondly, even though he later enjoyed lucrative factory deals with Honda, Kawasaki and Suzuki. “My TZs gave me the happiest time of my career,” says Grant. “I had a V6 Transit and a caravan, with a 250 and 350 in the back and a big box of spares. With that you went off and did GPs. They were good times. You got a couple of hundred quid start money, if you qualified, then you came home and did the British meetings. You could just about make a living and you had nobody telling you what to do. You just went where you wanted.
“TZs were reliable and easy to work on. I had a hydraulic press in the back of my Transit so I could rebuild cranks between GPs. You could have an engine out, fit a new crank and have it all back together in a couple of hours.
“It took me a while to work out how to get the best out of them. When I bought my first TZ350 it was a flying machine, but as the season went on it didn’t go so well. I recall seeing Jarno Saarinen [250 world champion in 1972] working late in his tent with his mechanic Vince French. I thought they were grinding away at the cylinder ports, but all they were doing was fitting new parts; that was the trick to keeping a TZ flying.
“The first TZ350 rewrote the rules for race bikes when it came out in 1973. It was the most unbelievably nice bike to ride. First time out I finished eighth in the Daytona 200; I was the first non-works rider. Later that year I was fourth at the Dutch TT and I never finished outside the top three in an international. You took the bike out of the crate, swapped the front drum brake for a disc, went down four sizes on the main jet and you could win UK championship races without batting an eye.
“It was John Cooper [former BSA rider] who offered me the 350, along with a 250. I told him I couldn’t afford them, so he said, ‘Pay me when you can.’ At the end of the year I went back with a big roll of cash and gave him £2500. I never looked back after that.”
But nothing lasts forever. Other firms wanted 250/350 glory, so the TZs came under increasing pressure from full factory bikes. First were Kawasaki’s KR250 and 350 twins, then Honda’s NSR250 and eventually factory bikes from Yamaha, Aprilia, Suzuki, Gilera and KTM. In 1982 the 350 class was dropped from GP events, drastically reducing the income of a 250/350 privateer. The (relatively) egalitarian age of GP racing was over.