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(Left) Borrowed from Guzzi's defunct eight-valve Daytona air-cooler, but with updated engineering, the 1225cc engine has a rev ceiling of 9000 rpm. (Above) The boxed aluminum swingarm looks purposeful, and it is, providing added rigidity to the MG's chassis. The shock, as do the forks, comes from Ohlins. (Right) Oz Racing wheels and 320mm Brembos with radial-mounted four-piston calipers are top-of-the-Iine equipment. "Our objective is to maintain the fully constructed to high levels of customer base represents. And one to its development. Now, with Aprilia character and identity of Moto Guzzi craftsmanship. We're a small facto- way to do this is by producing spe- in charge and a passionate guzzista while raising the level of quality," ry, and although our target is to pro- cial hand-built models like the MGS- but canny businessman like Ivano says Robert Brovazzo. "This means duce up to 20,000 bikes a year by 01 Corsa." Beggio at the other end of the check- we can think about making small- the end of the decade, we have Indeed, the MGS-Ol is the bike book, those days are over, and Moto volume hand-made models such as products which are different from that the Dr. John's BY Guzzi could Guzzi's idiosyncratic eight-valve hi- the MGS-Ol, which although they other manufacturers, and we realize have become more than a decade cam engine design is at least receiv- must inevitably cost more than vol- we must cater for the big club of ago but never did, thanks to De ing the R&D it was starved of from ume production bikes, will be care- enthusiasts for the marque which our Tomaso's reluctance to commit funds birth. Better late than never. TECHNICAL: [ffJDrfjrfj@[? D~ [ffJ@.(t(l@[? Ain't no substitute for cubes, say the good 01' boys in NASCAR country, so with putative AMA Superbike regulations allowing up to 1300cc in capacity for air-cooled twins, Guzzi's 35-year-old deveiopment engineer Giuseppe Ghezzi has pumped the MGS-01 Corsa's high camshaft 90-degree transverse V-twin eight-valve engine, dating back to 1988 in its original 992cc concept, up to I 225cc/l 00 x 78mm, from the one-liter Daytona/V10 Centauro version's previous 90 x 78mm configuration. "When the mechanical layout of an engine doesn't permit high revs, there's no replacement for increased capacity, and it was always my dream to build such a big-bore engine when I was racing Guzzis myself," says Ghezzi. "This is the biggest engine we can create with the standard crankcases." He's done this with the aid of 1Omm-oversize Cosworth forged pistons delivering 11: 1 compression, mounted on longer conrods fitted to the standard crankshaft, with many of the plain bearings in the stock motor now replaced by roller bearings and the oil system extensively reworked, especially to the big three-ring pistons, each of which now has two oil jets directed at it from beneath, for cooling purposes. The meaty new Gilardoni chrome-bore cylinders are also heavily finned, with the single camshaft per cylinder offset to sit alongside the valves and belt-driven by a single pulley mounted on a layshaft above the crank. The cams then operate the large-diameter nimonic valves (36mm inlets and 31 mm exhausts, up from 33mm/29.5mm on the stock 8V Daytona and each fitted with stiffer dual springs) via short pushrods and long rockers to reduce the height of the engine, making this not a true overhead camshaft motor, more an ohv design with composite cam drive via belt and pushrods. Ghezzi has ported the heads to increase flow, "But not beyond anything that a dedicated enthusiast could do, when fitting the racer kit we plan to sell to customers," he insists. He's also fitted the higher-lift cams from the 1000 Daytona racekit, matched to stock 50mm throttle bodies bored out to 54mm, still with a single injector per cylinder, and a cavernous 18.5-liter airbox of the size that twins need to breathe at their best. This is fed by a pair of airducts starting beneath the steering head then running within the chassis before exiting into the airbox casing. The engine management is entrusted to the same Magneti Marelli 15M ECU as Ducati employs on its 999 Superbike, which Ghezzi personally spent three days mapping on the Mandello del Lario factory dyno. Producing 122 bhp at 8000 rpm at the crankshaft (up from 94 bhp at 8200 rpm for the 992cc Centauro/Daytona) with a massive 83.5 ft.-ibs. of torque at just 6400 revs (and an equally amazing 65.3 ft.-Ibs. at just 2900 rpm), the bigbore motor is fitted with the VII Sport's six-speed gearbox, with a longer primary drive - the first time any eight-valve Moto Guzzi engine has had more than five speeds. Indeed, none of the Ghezzi & Brian II OOcc pushrod sportbikes ever had this feature, on account of previous Guzzi management's refusal to supply the six-speeder, meaning that this is the first time a Ghezzi-designed bike has been so endowed, complete with twin-plate dry sintered-bronze clutch with stiffer springs to accept the extra torque. However, in order t~ provide space for a vertically positioned fully adjustable Ohlins shock complete with rising-rate link - again, a first for any Moto Guzzi, with previous models relying on a cantilever shock bereft of any linkage - Ghezzi has turned the gearbox into a load-bearing component BMW Telelever-style, by bolting it on to the back of the engine, then incorporating within the casing the pivot for the beautifully made, 495mm long, fabricated box-section aluminum swingarm. This is another Guzzi first and in prototype form is made from five machined pieces of Anticordal aircraft alloy, "which took about a kilometer of ARC-welding to assembie!" says Giuseppe Ghezzi. This reduces the wheelbase of the rectangular-section steelbackbone chassis significantly, from the previous 8V Daytona's 59 inches to the MGS-Ol 's 57 inches, same as an Aprilia RSV-R Superbike, while delivering a longer swingarm than is usual on a Guzzi to enhance traction and rear grip RIstyle. Worth noting that the chassis is a true monocoque frame, with the 4.7-gallon fuel load contained within the upper spar and twin engine supports in order to provide maximum space for that huge air.box. The 43mm TIN-coated Ohlins upside-down forks are set at 23.5 degrees on this prototype, with 95mm of trail and 4.8 inches of wheel travel, though more noteworthy is the 4.4 inches of rear wheel travel, in spite of the shaft final drive that has previously dictated ultrastiff shock springs on monoshock Moto Guzzis. On the MGS-Ol, this incorporates a parallelogram linkage similar to that first developed on the Dr. John's Guzzi, to dial out most of the pitch back and forth, and rise and fall on the suspension, so typical of shatties. Brakes are top-level 320mm front Brembos with radialmounted four-pot calipers, which just as the forks are a straight transplant from the 2003-model Aprilia RSY Mille, eN with a 220mm single-caliper rear, while the ultralightweight five-spoke wheels are OZ's latest forged design, saving a huge 6.6 Ibs., or 25 percent in unsprung weight, over conventional cast equivalents. This allows the MGS-O 1 to scale in at a claimed 422 Ibs. dry, complete with carbon bodywork, split 50/50-percent static - not bad, considering the engine and gearbox together scale in at 204 Ibs. on their own. Interestingly, John Wittner claimed 347 Ibs. dry with a 55/45-percent frontal bias for his 8V Guzzi BoTT racer - maybe a trifle optimistic, but the street Centauro 8V weighs(ed) in at 451 Ibs., so the minimalist-looking MGS-OI looks like it still has some way to go on its diet. That meaty-looking 60mm-diameter exhaust system is made in stainless steel, for example, so a titanium version would lose some weight, as would a carbon shroud for the prototype under-seat silencer, which on the Serie road bike at least will be a more Ducati-esque oval shape, probably by Termignoni. But that's all in the future, and what matters now is that the prototype MGS-OI Corsa is up and running, and under development. "Our goal was not to develop too extreme a bike for our customers to buy," says Giuseppe Ghezzi. "We aim to provide a good basis for tuners to extract more performance from the machine if they wish and to reduce the weight, all in pursuit of more performance. But what matters to Moto Guzzi is that we deliver a reliable, well-made product to our customers, and the fact we've spent three days of dyno testing, two Monza test days and two more here at Adria, all with the same engine in the single running prototype we have yet built without having to do anything more than change the oil and check the valve clearances, gives me some confidence we're on the road to doing just that." And finally to fulfilling his dream of building a bigger, better Guzzi? "Look, I've spent all my life building stuff that I liked working on. Now it seems I get to share that enjoyment with others and get paid for doing so by creating bikes that will be manufactured in the Mandello factory to Aprilia's levels of quality and reliability, which I know will bring pleasure to guzzisti like me around the world, and others besides. This bike is a new page for Moto Guzzi, and it's very exciting to be part of it all." eye I e n e _ S • AUGUST 27,2003 51