Cycle News - Archive Issues - 1990's

(airing flanks not only deliver a more aerodynamic aspect by covering up the rider's knees, they also contain internal ducting feeding forced air to the rear cylinder, thus dropping oil temperature 70 degrees lower than before, says development engineer Andrea Forni. There's a good-sized oil radiator above the front cylinder, monitored by a temperature gauge on the dash. However, the major design debt owed to the Supermono by the new Supersport is less appar-ent: The seat-tpfootpeg-to-handlebar ratio. The result delivers a seat height 1.6 inches h.igher than on the old 90055, with rear-set footre~ts .4-inch higher, resulting in a sporting stance tbat doesn't put undue weight on your wrists and forearms, yet is reasonably aerodynamic at speed. You'll not find another sportbike more comfortable to ride around city streets well, apart from the traditional stiffaction Ducati clutch. Some things never change. But thanks to the 900 Supersport's nimble build and rational riding stance, and despite the low-cut screen, it's also relatively untiring at 120-plus mph. The almost imperceptible reversecurve. upper lip to the screen diverts high-speed airflow onto your chest, where it helps take the weight off your arms, yet it also gives a surprising degree of protection, especially in the rain, if you squat flat on the tank. It's more effective than it appears, and Ducati claims a top speed for the bike of 140 mph, which - judging by the 120 mph at 7500 rpm I saw on this Britishspec bike - seems right. The 900 Supersport is also a true twoseater, in a way a hypersport bike like the 916 or R1 will never be, complete with soliq grab handle and footpegs that I'm assured are not so high as to be unduly cramped. Pity there are no clipon points for luggage, though, and, while niggling, let's bemoan the anonymous appearance of the bike, with just a single small Ducati tag on the fairing. Adding to the anonymity is the bland appearance of the black-faced instruments, which could have been lifted off almost any Japanese-model bike. Expect a strong aftermarket for white-faced Veglia tachometers, as well as carbon Termignoni or titanium Akropovic silencers to replace the massive, unlovely things that come stock on the end of the twin exhaust pipes. They do at least achieve their objective of waving the 'Supersport past the noise police. The 900SS sounds pretty quiet by two-valve Ducati standards, though still completely distinctive - Honda and Suzuki may have copied the 90-degree V-twin engine format, but they still ain't got The Sound.... The uprated SOHC 92 x 68= engine in the 900 Supersport is less of a slugger and more of a revver than the old, 90055 ever was. Partly this has come flom internal modification, partly from the adoption of fuel injection, which (just as on the STZ) delivers a degree of precision combined with a sharpness of response and a light throttle action, all of which the old carbie bike never had, liven fitted with aftermarket Keihin flatslides that gave you the crack but not t£le control. ,It'll pull cleanly on part-throttle as low as 2000 rpm in the bottom three ra~os, and from 2500 revs in the upper three, all without any of the sometimes horrific transmission snatch that would greet you if you tried the same thing on the old 900. Engine-management mapping is largely responsible for this major improvement in low-down ridability that makes the Ducati now as easy to ride on city streets as a Japanese twin excepting, again, for that heavy clutch. This, howe~er, does take up more smoothly than before, even winding it up hard off the line at a Traffic Light GP. Once in econd gear, though, a new selector drum means you can forget about having to us~ it to upshift, so improved is the chang~ action of Ducati's six-speed gearbox. . The best compliment I can pay this transmission is that it's now as good as anything made 'in Japan, in the way it shifts sweetly between ratios. Unfortunately, these are the same as on the old 90055, with quite a gap (about 900 rpm) between fourth and the top two gears, both of which are overdrives. This was barely acceptable on the old carbureted bike, which was essentially overgeared to take into account the fact it peaked at 7000 revs and didn't much like to rev a lot higher in' stock form. Simply put, the ratios should have been altered on the new Supersport - it's only a question of punching in a different program on the gear-cutting tool, after all. Running two overdrive gears in this day and age is positively archaic - it saps power and, as many customers will attest, tears up the gearbox hardening (especially on a torquey bike like a Ducati, whose punch encourages riders to accelerate hard from low down in higher gears). So why not fix it along with the rest of the bike? The 7-bhp power increase delivered 500 rpm further up the rev range on the Supersport - provided by the combination of EFI and revised valve timing, with new camshafts supplying more lift and duration, as well as the wider usable powerband down low - makes a more appropriate set of ratios, with a 1:1 top gear, the must.Jtave next thing on Ducati's checklist, and anyone who's ridden an old 90055 fitted with an aftermarket close-ratio gearbox will agree. \Still, even with the improved lowdo';wn horsepower of the Supersport eng me, owners won't have to think about gearing it down by fitting a bigger rear sprocket to make the bike more ridable in town, as so many did on the 900SS, because Ducati has already done it for them. The Supersport wears 15/40T overall gearing, against the overgeared old 9OOSS's 15/37T, and the new bike's substantially improved acceleration and low-speed traffic manners are the result. But while the new Supersport is all about added response at almost any revs, running in a line of traffic at 4000 rpm in third gear and spotting an overtaking gap delivers the best illustra tion of its vastly improved pickup. Just gas it up wide open and feel the waves of V-twin torque come on stream (peak is 53.8 ft.-lb. at 7000 rpm), as the engine surges cleanly and irresistibly toward the gray-face tacho's nonexistent redline. At 5200 rpm there's an extra kick of power as the engine accelerates still harder, tailing off above 8000 rpm when the motor starts to tell you it might be a good idea to change up before hitting the soft rev limiter at just over the nine-grand mark. In practice, out on open roads it feels best to use that smooth-shifting gearbox to keep the Supersport revving in the upper midrange between 5000 and 7500 rpm, where it seems most at home - but Ducati has sacrificed nothing at all in spreading the old 90055 motor's punchy midrange poke out in both directions on the tacho. The power delivery just got better - but, still, it could be superb, once Ducati gets around to redesigning the aging SOHC cylinder heads that are still the biggest barrier to a real performance increase on the desmodue motor. Eighty bhp from a fuel-injected V-twin may be 10 percent more than the old 90055, but it's not any better than many tuned singles, thanks to the head design dating from the Taglioni era 20 years ago when the Pantah first surfaced. Once Ducati delivers an uprated version of the Supersport engine with a flatter valve angle, as well as steeper ports that have been lifted to give more downdraft, the analogy with Porsche's air-cooled Boxer engine tha t Massimo Bardi is so fond of making in relation to Ducati's "classic sport" two-valve range may be more appropriate - because the Germans never lagged behind in cylinder-head design the way Ducati has. Though visually similar to the old 900SS's tubular-steel space-frame, the Supers port chassis is substantially revised and feels immediately diffe~nt to ride on, at almost any speed. The ,more radical steering geometry (less trail, one-degree steeper 24-degree head angle and raised rear ride height) is mainly responsible for this, but together with the .6-inch-shorter wheelbase and increased front-end weight bias (partly obtained by parking the rider higher up, with relatively low handlebars), the result is a bike that steers and handles as well as any superbike on the road - honestly. You have much more confidence in what the front wheel is doing than on any air-cooled Ducati yet built, where the lack of a heavy four-valve cylinder head with eight rockers (as on the 916) or any water radiator meant that previously there has been a distinct rearward weight bias on all two-valve desmos. That meant setting up the suspension was always a bit of a compromise, and getting the front tire to stick properly in fast turns was not always something you could rely on. The chassis package of the new Supersport goes a long way toward resolving that problem, and the result is a bi[

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