Cycle News - Archive Issues - 1990's

Rumi to grow EUROFILE BY ALAN CATHCART Another Triumph? Triumph has a sporty new design for the Thunderbird family under development, due to be launched at the Paris Show in September - but factory sources insist it isn't tuned up in the way the Numero Tre Super Sport (see box) is. Instead, the model, code-numbered T309 (also known inside the factory as the RD), uses the same 73-bhp version of the original 900c{: three-cylinder engine as the T-Bird, fitted in the same EgJi-type spine frame, but with flattrack-styling derived from the Trackmaster oval-speedway racers built to house the old Triumph Bonneville engine two decades or more ago. The flat handlebars resemble the Numero Tre special's riding position, with a neat, stripped-down look to the seat and a smaller fuel tank to deliver a cobbier, sportier look than the more retro T-Bird or the Adventurer cruiser. Word is that the T309 was actually ready for production in 1997, but that Triumph management pulled it back at the last moment in favor of trying to ride what was perceived as the streetfighter craze with the radically styled, stripped-down T509 Speed Triple, launmed in tandem with the bike it was derived from, the bigger-bore T595 Daytona. This might have seemed like a good idea at the time, except for three things: One, the streetfighter craze hasn't happened - yet, if at all. It's still an example of two-wheeled radical chic. Two, the T509's aggressive styling is a love-it-orhate-it experience - and it could just be that it deters more people from buying an updated Speed Triple than it encourages to buy a streetfighter. And three, the T509 is being blitzed in the showrooms by the fabulous T595 Daytona, which overshadows it in every way. In retrospect, it seems a smarter move would have been to launch the T309 (and perhaps call it an Ascot after the famous half-mile Speedway near Los Angeles, where so many Triumph race victories were won) for this model year - especially to prop up the Adventurer, which hasn't exactly set the cash registers ringing -, and to have held back the T509 Speed Triple until '98, to allow it to star on its own instead of being overshadowed by the new Daytona. Hey - maybe Mr. Bloor doesn't get it right every time, after alljust most of the time. However, he just might if he says yes to the next major decision Triumph is now facing: whether to go head-to-head with the Japanes'e in another major street bike category, and try to match the sales success of the new Daytona by building a three- or four-cylinder 600cc supersport contender, using technology derived from the bigger bike. Contrary to reports in the British press, no definite decision has yet been made regarding a 600cc supersport, say Triumph factory sources - but a concept bike has been built in mocku p form by stylist John Mockett and his team, and Bloor and his executives are close to making a decision about whether to proceed with development. If it goes ahead, Triumph would plan to launch the bike in 1999 for the 2000 model year, in a form closely derived from the T595 Daytona, complete with Sagem EFI and tubular-alloy frame. However, the moice of whether to go for a four-cylinder 600 like all the Japanese companies, or a 680cc triple notionally permitted under FIM supersport rules has also to be made. Triumph is reluctant to sacrifice its individuality by dropping its trademark three-cylinder format, but at the same time doesn't want to risk not being fully New Laverda production on line In Europe and the Supersport World Cup, at least, a 600cc Triumph would have to compete with the 750cc twins current!Y. dominating the class thanks to Ducati - but now there's another Italian twin about to join the fold: Laverda. Launched in prototype form at the IFMA Cologne Show last October, the Laverda 750 was announced as being scheduled to start production in September of this year - but that's turned out to be a typically Production of the Laverda 750cc parallel twin is canny trick by company boss ahead of schedule and should start sometime France5{:o Tognon. during April. A sport version is to be produced "Too often in the past Italian for use in supersport racing. manufacturers have annotmced a new model, then suffered an unacceptable delay before getting it into production," he says. "At Laverda, we prefer to surprise the customer by actually bringing the new model to the marketplace sooner than he expected us to." Hence the fact that the new liquid-eooled 750cc twin, 80 percent of the engine of which is all-new compared to the elderly air/oil-cooled 650'that powers Laverda's existing range, will enter production in April. Produc~on will come in two forms, the 78-bhp base model which provides good t.Qrque and a wide spread of power for everyday riding, and the uprated, revvier S-version delivering 92 bhp at 9000 rpm, with a narrower powerband and rev limiter set at 9400 rpm. A tuned version of this sport version will be entered in the Spa 24-hour and Bol d'Or 24-hour races this year by Laverda's Belgian importer - but in the meantime Laverda's development team headed by chief engineer Nicola Materazzi is working hard on a supersport sprint version of the bike to be ready for the 1998 season, with a target output of 115 bhp delivered by five-figure revs from the fuel-injected 180degree parallel-twin engine. This has a much stronger crankcase design than the existing 650cc motor, as well as being much lighter. For instance, the new 750cc cylinder head weighs seven pounds as a machined casting, compared to 21.1 for the 650 head! Tognon says he's already very pleased with the performance of the 7505 road~ ster, which in side-by-side tests has already shown it can outrun a Ducati 748. Imagine a twin-cylinder doubled-up Ducati Supermono (there's a contradiction in terms!), but with a fuel-injected DOHC eight-valve parallel-twin non-desmo 'motor, complete with laydown cylinder block, extractable gearbox, a meaty dry clutch on the right side and fat, 54mm throttle bodies for the Weber-Marelli EFI poking near-vertically upward into a sealed airbox behind the steering Ruml has built a laydown twin before - pictured is a 1953 head of the tubular steel 125cc DOHC twin - and it looks as though the company spaceframe chassis. will build one again. Trick - or what? No, it's not Yamaha's answer to the new Honda and Suzuki V-twin roadsters, but the latest in the seemingly endless succession of new Italian superbikes to make it· into metal - the Rumi 1000 Bicilindrica. Since I first'revealed its existence back in October 1993, the progress of the Rumi Superbike I?roject has faltered, for tragic reasons - but now it's back on line, and the first prototype has at last been completed, ready for testing. As the man whose team took Honda and Fred Merkel to two successive World Superbike titles in 1988-89, Oscar Rumi is the best known today of the bike-mad Rurni family from Giacomo Agostini's horne town of Bergamo, but it was his uncle Domno who created the Moto Rurni marque back in the 1950s as a sideline from the high-tech steel foundry empire that's the basis of the family fortune. Its 125cc Formicino ('Little Ant') was a best-selling twin-cylinder two-stroke scooter long before the new Italjet Formula 125 was even thought of, but in 1962 Donino Rurni closed down the business for personal reasons, and for three decades there were no more Rurni motorcycles. But in 1992 the late Donino's son Stefano and grandson Donino revived the Rumi name with a Jan Thiel-designed 125cc GP racer which, however, proved uncompetitive in the '93 GP season in the hands of Stefano Caracchi. Instead, encouraged by the Superbike success of his cousin Oscar's team, Stefano Rumi embarked on development of a 1OO0cc parallel-twin four-stroke engine, with which he planned to relaunch the Rurni name on the world stage. Those plans were cruelly set back by the tragic death of son Doruno in a car crash in 1995 - but primarily as a tribute to his memory, Stefano Rurni has kept the project alive, and development has recently accelerated. The Rumi marque is now on course to be relaunched at the Milan Show in September, with two new 1oo0cc fourstroke models: a fully-faired Superbike most probably to be named the Doruno, which it's intended will be built in sufficient volume to qualify it for World Superbike racing in 1999, and a naked roadster likely to prove an upmarket, more exclusive rival to the Ducati 900 Monster. Both these new bikes will use the same tubular steel spaceframe design, from which the compact engine is underslung to form a fully-stressed chassis member just as on the Ducati desmoquattro single, but with Segale/Yamaha TRX overtones in the form of rear engine plates milled from billets of aircraft alloy, in which the conventional (not single-sided) extruded aluminum swingarm pivots. The laydown motor means the Rumi Superbike is likely to have the same nimble handling as a Ducati, 1IVi.th the reduced frontal area delivered by the cylinders being raised just 15 degrees from horizontal, offering improved top speed, as well as better handling over bumps thanks to the low center of gravity. Unlike the cantilever rear end on the desmo single, though, there's a rising-rate linkage for the horizontal rear shock, which is similarly located over the six-speed gearbox; on the Rurni, this has a side-loading extractable gear duster for quick ratio changes. Steering geometry is adjustable· with conical inserts in the steering head. In spite of the forward-facing cylinders, the Rurni twin has a contained wheelbase of 56.3 inches, thanks mainly to the very oversquare 997cc engine's dimensions of 102 x 61mm - same as rumored for the forthcoming Moto Guzzi Superbike currently also under development. This means the Rurni is likely to be a revver, but sources within the company are tight-lipped about rpm and dyno figures (expect upward of 12,000 rpm with such a short stroke), as well as the crankshaft throw: It's not dear whether the engine is a 360-degree (two-up) parallel-twin, or a 180-degree (one-up, one-down), or perhaps even has the crank rephased to a 90-degree/270-degree layout as on the TRX Yamaha. Either way, there are reportedly two gear-driven balance shafts to reduce vibration, while like the V-twin Harley VR1000 and Honda VTR1000 engines, the drysump Rumi parallel-twin motor has the cylinders cast in unit with the crankcase halves, for extra stillness. Drive to the eight-valve cylinder head's double overhead camshafts is by a train of gears (not belt or chain) up the left side of the engine. Apart from a solitary DOHC four-stroke conversion to a late-'50s Rurni 125cc twin that today appears in Swedish historic events, and the Honda-based Supermono twin-cam built by Oscar Rurni a couple of years ago, all Rurnis that have so far taken to the tracks have been two-strokes. The 1000cc Bicilindrica will be the first Rumi parallel-twin four-stroke - but looking at its specifications and likely performance, you can't help asking yourself if this isn't the motorcycle that Norton should be building today. competitive performance-wise in a horsepower-driven class - and that means a target of 110 bhp to be competitive come 2000, without sacrificing ridability. Another factor in fa vor of the fourcylinder route for the T600, as the project is code-numbered, is that the biggest supersport market in the world_ is the United States, where the AMA doesn't recognize the FIM-approved capacity breaks for twins and triples. If Triumph wants to show off the performance of its supersport contender in U.s. racing, it would have to build a 600cc four. Chances are tha t, if the project goes ahead, that's what Triumph will opt for.

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