The Yamaha TZ250 was introduced in 1973, and was soon filling grids in 250cc world championship races.
In the 70s and early 80s, the Yamaha TZ250 dominated 250 Grand Prix racing pretty much the world over. Introduced in 1973, the TZ was a water-cooled evolution of Yamaha’s popular TD and TR air-cooled production track-only machines. Its moderate price tag made it attractive to club-level racers, and a strong aftermarket with plenty of go-fast upgrades helped make the TZ competitive at even the Grand Prix level for a number of years.
Yamaha TZs in various sizes saw success in other classes as well. A 350 model was introduced at the same time as the 250, and was practically identical but for larger cylinders. Two of the 350’s paired cylinder blocks put on a common crankcase created the original TZ700, which later grew into the TZ750. When the 250 was produced in the 80s with individual 125cc cylinders, it spawned TZ125 and TZ500 models as well. Other manufacturers produced their own production racebikes at various times (the Suzuki RG500 and Honda RS series, for example), but the TZ250 was a popular choice for racers for more than 30 years. That is a long lifespan for any single model of motorcycle, and especially so for a production racebike. A lot of riders won a lot of races and championships on the various TZ models; all three of us here at the magazine — Kent, Bradley and I — raced TZ250s at some point.
One aspect that kept the TZ’s price down for many years was that it was sold in a quite basic specification and almost relied on that strong aftermarket to be competitive. For example, my brother’s TZ250F model (which he bought new in 1979) had spoked wheels and Yokohama tires that were almost immediately replaced with Dymag cast wheels and slick tires. Likewise, the stock Mikuni carburetors were jettisoned for a pair of Lectrons. In the TZ’s heyday, a multitude of aftermarket companies provided all kinds of upgrades. Bimota, Harris, Spondon and dozens of other companies manufactured frames and chassis bits, while Harold Bartol, Hans Hummel and others made engine parts, including complete cylinders. Later versions of the TZ came in a more competitive state, but you could still improve upon them with engine, chassis and suspension work.
For almost all of those years of success, the TZ250 was based on a production motorcycle. "
How, then, does the TZ relate to the current predicament of MotoGP and the Claiming Rule Team structure? For almost all of those years of success, the TZ250 was based on a production motorcycle. Early TZs used the crankcases and many bottom-end parts from the RD350 engine, as well as chassis parts from other production Yamahas; this too helped keep the price reasonable for many years. In 1981, dedicated crankcases were introduced and the TZ grew apart from its production roots, but many of the bike’s parts were still production-based. 10 years later, the V-twin models began using cases and engine internals from the TZR250 streetbike.
Years ago, few riders could expect to get on a Grand Prix podium with a TZ250, but it would at least get them on the grid and in the race without breaking the bank. From there, they could prove their mettle and hopefully move up to a factory ride. Likewise, I think that is the most important aspect of the CRT rule: to get more riders on the grid gaining experience in the class and looking forward to the future. The bikes don’t have to be capable of winning, nor do I think they should be given rules advantages to make that possible. If a good rider on a CRT entry can get in amongst the satellite bikes and be noticed by the factories, I would consider that a success. For a rider new to the class, it will take a fully developed, reasonably priced, ready-to-race machine to do that.
I have to think that at least Yamaha, for years the privateers’ choice in GP racing, will at some point step forward with a production-based turn-key CRT machine for the MotoGP class. The difference between now and 1973 is that the TZ250 could be raced almost anywhere — practically every club and national series offered some kind of lightweight Grand Prix class. That sheer volume is another big factor that kept the TZ’s price in check over the years. The market for a liter-sized GP bike right now, unfortunately, is only in MotoGP.
Currently, only Aprilia is offering complete bikes to MotoGP teams. The aftermarket is as strong as ever with a number of companies all capable of making a competitive chassis, but in the present age of advanced electronics and materials technology, the factory retains the upper hand — especially in the electronics department. One of the rules packages being proposed for 2013 has MotoGP switching to an all-CRT format and prototype bikes eliminated, but I would much rather see other manufacturers offer complete racebikes for sale to teams and the CRT concept naturally — rather than forcibly — gain in popularity. SR