Cycle News - Archive Issues - 1990's

G iacom oAgostini and the 500cc MV Agusta Longt ime Grand Prix mechanic Nobby Clark (left) and Team Obsolete team owner Rob Iannucci (right) pose with the tom-apert MV. pieces from ove rhea ting and seizin g up under the stress of Grand Prix events. However, in 1974 a tw o-stroke won the 350cc wo rld cha m pionship for the fi rs t ti me wh e n Agos tini, w ho h ad moved from MV,.took the title on Yama ha's TZ twin. A year later, MV lost control of the 500cc class for the first time since 1958. Suzu ki scored their first wins in th e class w ith th eir four-cylind e r RG500, and Yam aha claimed the world championship with Agostini riding their two -stroke four. MV was in deep trouble. Phil Read , the Englishman wh o had given them the 1974 500cc champion ship, had fled to Suzuki . New directors, less sympathe tic to motorcycle racing than an earlier generation, we re in control of the company. The FIM, Gra nd Prix racing's governing body, was threaten ing to impose noise rest rictions that w ould hurt four-stroke engi nes more than two-strokes. And an experirne nta l flat-four engine, d esigned to pu t MV ba ck in fro n t of the twostrokes, was provin g tr oublesom e in ben ch tests. But incred ibly, MY tempted Agostini back to race th e 350 a nd 500 cc fourcylinder bikes on his own privat e team, with lim ited techn ical backing from the factory u ntil the flat-four could be properly developed. It took only weeks for the deal to go sour. Against the Yamah as and Suzukis, the MVs were uncompeti tive. "Until 1 get m ore speed, " Ago st ini fum ed, "I ha ve no chance o f w inn in g," and he pledged to rid e an RGSOO Suzuki for the rest of the season . VICTORY AT NURBURGRING o Agostini's Suzuki commitment lasted u ntil he arrived at the Nurburgring for the West Germ an Grand Prix. In the 70s the race was held on a notoriously d angerous 14.2-mile, 170-corner circuit in the Eifel mountains. And it looked like it was going to be a damp weekend... "I tried the Suzuki and the MV in practice. The Suzuki had more power, but it was more d ifficult to rid e in the MV vs. Suzuki • 1976 uzuki achieved their first 500cc Grand Prix race wins with their radical new RG500 square-four two-stroke in 1975. By 1976 - when Agostini ha d to choose between the two bikes at the Nurburgring - the RG was more powerful than the MV, but also slightl y heavier. But it was a turning poin t in the sport. The MV recorded only one win that season, wh ile Barry Sheene rode the RG to the wo rld cham pionship in 76 and '77 . Two-strokes have dominated the Grands Prix ever since. S MV Suzuki Engine In-line four-cylinder four-stroke Bore x stroke . .57 x 49.4mm Induction Gear-driven DOHC four-valve heads Cooling Air Fuel system (4) 32mm Dell'Orto carbu retors Ignition ' M ercury magneto bhp 106@ 14.0 00 rpm Gearbox s-speed Frame Tubular steel Forks Marzocchl Rea r shock M arzocchi Front brake . . .Dual discs Rear brake Single disc Wheels 18-in. dia. Weight 275 Ibs. Top speed 182 mph (est) Square-four tw o-stroke 54 x 54 four rotary valves Water (4) 34mm Mikun i carbure tors Nippon-Denso magneto 114@ 11,00 0 rpm 6-speed Tubular steel Kayaba Kayaba Dual discs Single disc 18-in. dia. 290 Ibs. 183 mph The bike was about 10 bhp down on the ri val RG500 Suzu ki, but about 15 pounds light er. In the 70s it was said to be a 180-mph motorcycle, although it's hard to rel y o n th ese clai ms w hen today's world cha m p io n sh ip 500 cc Honda, w ith some 70 horsep ower m ore, jus t nudges 200 mp h on a superfast circuit. So how doe s this chunk of his tory in aluminum and steel run and sound? "I d on 't know - we've never star ted it," Iannu cci admi tted, as Ago's former mechanic No bby Clark com ple ted preDaytona preparation of the bike in Team Obsolete's Brooklyn workshops. " Bu t th er e s ho u ldn 't be a pro ble m. W e str ipped th e m o to r and p ressed the cra n kshaft apart, but all we had to do wa s clea n everythi ng up, hand-p olish the journals, de-glaze the cylinders and lap th e valves. The va lve sp rings and clutch pl ates a re th e onl y new parts we've put in the bike. "We touched u p the fairing paint by han d, an d Agostini has sup plied some m issin g d eca ls. We re p lace d th e swing a rm bearing s, r ebu ilt th e hydraul ics and had the Morris magn esium wh eels X-rayed and repa inted by Marchesini in Italy." The Team Obsolet e circu s has been granted a special demonstration spot on each of Daytona's two vintage da ys on March 4-5. Agostini will get the chance to s p li t th e sky on ce more with th e scre a m of that unsi lenced 16- val ve , tw in-cam motor, and former 250 and 3500cc Grand Prix champion Jim Readman will repeat his showcase rid es of last yea r ,on the amazing Honda Six. In ad d ition, Don Vesco will ride a r ar e 1967 MY 500 triple. If you' ve never heard th ese unrestricted four -stro ke Grand Prix we apons in ac tion before, m a ke it to Dayton a. And forget that ear protection - just listen to the music. 0" The technology war The two-stroke advance First Grand Prix ra ce w ins 50c c 1962 Hans-Georg Anscheid t (Kreidler) 125cc 1959 Em st Degner (MZl 250c c 1952 R. Felgenheier (OKWl 350c c 1966 Phil Read (Yamaha) 500c c 1971 Jack Findlay (Suzuki) First world championships 50 cc 196 2 Emst Degner (Suzukt) 125cc 1963 Hugh Anderson (Suzuki) 250 cc 1964 Phil Read (Yamaha) we t, and I thou gh t I could wi n on the MY." It rained on race m ornin g, and Agostini chose the four-stroke. It was the correct decision , as he ro de away fro m a field of Suzukis and Yamahas, with the Italian rider Marco Lucchinelli in second place and American Pat Henn en in third. ' Probably few peop le at the Nurburgring gu essed th at th ey had just witnessed a turning point in histor y. MY Agu sta, it seeme d, had always been in racin g, always man aged to keep on winning. Only now , with the luxu ry of hindsight, can we realize that any Grand Prix tha t MV won in 7 6 w as likely to be a final success for four-stroke technology. THE "DAYTONA" MV The bike that Team Obsolete will run at Daytona represents the peak of MY's devel opment of four-stroke engineering. After Agost in i' s com p laints earlier in 1976, tea m ch ie f Arturo Ma gni improved th e bike u ntil it develo pe d around 105 bhp at 14,000 rpm . "Tha t' s an in cr edible acc omp lish ment wit h the technol ogy th ey were using," Iannucci points out. "They were still using air coolng, fixed ignition timing and carb ure to rs . Tod ay, you need wa ter cooling, electronic ignitio n and fuel injec tion for re ally se r ious fourstroke power." Compared to ea rlier MVs, the bike ha s na rrow-angle cylinder heads, with the angle between the valves reduced to achiev e shallower combustion chambers and more of a downdraft-carburetion effect. Magni's team also relocated the gearbox to pl ace the output sp rocke t about 1.5 inches lower than on previous MVs, to p re ven t th e rear wheel from chattering under deceleration . 350cc 197 4 Giacomo Agost ini (Yamaha) 50 0cc 1975 Giacomo Agost ini (Yamaha) The four-slrqke retreat Last Grand Prix race wins 50cc 1966 Luigi Tavert (Honda) 125cc 1966 Luigi Taveri (Honda) 250cc 1969 Kel Carru thers (Benelli) 350cc 197 6 Giacomo Ag ostini (MVJ 500 cc 1976 Giacomo Ag ostini (MVJ Last w o rl d championships 50cc 1965 Ralph Bryand (Honda) . 25cc 1966 Luigi Taveri (Ho nda) 1 250cc 1969 Kel Carruthers (Benelli) 35 0cc 1973 Giacomo Ago stini (MVJ 500cc 1974 Phil Read (MVJ

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