Cycle News - Archive Issues - 2000's

Stefan Everts' Yamaha YZ450 FM and YZ2 50FM HE VZ450FM the machine that m uch further." Due to th e fact that racing at fac tory level m eans that ultimate performance must be the goal . the Rina ldi techn ic ians hav e wo rke d hard to produce a bike ca pable of pe rforming at the very highest lev el of the sport. To do th is , t h e focus was not put so m uch on serious performa nce gains, instead on fine-tuning the eng ine to sui t the needs of the team 's riders. "A s a result the num ber of special parts is relatively modest for an official factory machine," reckons Yamaha . CHANGES FOR THE BETTER ". By YZ450FM (M is the fa -ctory de'sig'nati o'l for m od ified) and his YZ250F were also there to be ridden made for an unforg ettable da y. Being abl e to rid e " Ste fa n 's bikes " was the ic ing o n a cake that only a han dful of very luck y indivi duals wer e getting to sample. J O NT Y E D MU NDS PHOTOS BY YRD A ND P AU LO C ARRUBBA don 't know why, but for me there's always been something sp ecial about being able to get up close and personal with an "official " Wor ld I BLUE I S BEAUTIFU L C hampionship-wi nni ng motocross bike. E v er s ince I firs t caught a glimpse of a fac to ry rac er, I've always No matter wh ich angle yo u look at Stefan 's YZ4 50FM from , it's beautiful. A bsolute ly beautiful. Wi th it s disti nc ti ve blue and red L&M livery, stri k in g black -pai n ted fra me and blac k found th e a ll u re of a G ran d Prix mot o cr o s s b ik e j us t t o o h ar d to ignore. No m atter what the class. no One rider and one bike 'have dominated the MX GP class this year - Stefan Everts and his YZ450FM Yamaha. Invited to northern Italy to test the championship-winning machine, we put Stefan's 72-numbered machines t hrough their paces and like what we find. ma tter what the capacity , and no matter who the rider, being able to gaze lo ngingly at a well- prepared fac tory bi ke is, to m e, somethi ng wo rt h payi ng good money for. An invitation to spe nd th e day as a gu est of the L&M Yam aha Motocross T eam i n Italy w a s t h e ty pe th at nobody needs to be offe red tw ic e. " Of course I'd love to go," I replied as I grinned from ear to ear. With both team prin c ipals, Mi ch ele and Carlo Rinaldi, all th e team 's mecha nics and technicians, oh , and one M r. Stefan Everts on hand to talk about the remarka ble season that '03 has been for both Yamaha and Stefan, the fac t that both Stefan 's MX GP title-winning 32 OCTOBER 22 . 2003' cue nevvs '" The author, here aboard Stefan Eve rts ' championshipwin ning VZ45OFM. was very impre ssed w ith the bike. wheels . th e bike looks eve ry bit th e World Champio nshipwi n ning ma ch ine it i s. B u t stri p aw ay- all the bri gh t l y colored pl astics and carbo n fi ber guard s. and yo u ,have a m ach in e tha t is 10 times cl o ser to a product ion b ik e tha n either of St efan 's 500cc cha m pionshi p- w inni ng bikes . from ' Ol a n d ' 0 2 . With no sp e c i al alum inum c ha s si s or in cr eased engine capacity , it is easy to see that fine -tun ing, and not seri ous p erformanc e enhancements, is where the team 's energies have been focused th is year. But you wou ldn 't expect Stefan Ie - Everts to liave won the ' 0 3 MX GP title on a stock bike - and he didn't. . While the bike 's architecture is ve ry similar to a p roduct ion YZ450F some of it is in fact identical - the bike does feature numero us changes and features several special parts, not least the factory Ka yaba suspension and Brembo brakes . If Yamaha's m otoc ross press kit is to be beli eved , th e ' 04 YZ450F has been both an easy and d ifficult bike to prepare for MX GP co m pe t iti o n . Easy b ec au se acc o rd i n g to t eam manager Michele Rinal d i the produc tion bik e, on wh ic h th e YZ450FM is ba sed . alr ead y has a " very well-balanc ed eng ine and chassis." And diffi c u lt because i t w a s therefore " n o t easy to ra ise the competitive level of But those special parts replace many of the eng ine 's major co mponents . Piston. con-rod . cy linder and crankshaft a r e all " sp ec i al " YRRD parts helping the engine produce a powe r curve that shows increased performance over the ent ire rev range, something that is also i n pa rt achieved by fine- tuning the cylinde r head and carburetor. With a YR RD ignition that features un ique mapping, giving an even smoothe r -feeling engine . the team also does " a little work to the cylinder head " and uses different ca ms . In fact they have m an y d iff erent ca m p o ss ib iliti es, it j ust depends how th eir ride r lik es his moto r to feel. Com pa red t o th e st andard YZ4 50 F ca m, th e on es fitted into Stefan 's bik e help th e m otor pr oduce a stronger m idrang e - j ust th e way he likes a m ot or. You do , howev er , get a • 'V" little b it more to p-end pow er , one of the te am's mechanics po int ed o ut. "You don 't normally go int o the to p powe r th ou gh ," he also explained. t While t he e ngine does featu r e many cha nges over standard . one area of t he bike tha t doesn 't is the c h a s s i s . M i r r o r i n g the productio n sp ecific ati ons and in a departure from the alum inium YZ500FM ch assis used last yea r, the team now uses a stan d ard YZ450F frame . with una ltered • geometry. The only m od ifi c atio ns are ' the bi k e's le ngthe ned swing arm fo r im proved sta bility and better starts th ey w ould n ' t tell me ex ac tly how '" much long er it was - a few altered brackets to ac c ept a sum p guard, and Brembo rear bra ke m aster cy li n de r and mach in e d tripl e c l a m ps t h at m o d i f y the o ff se t of th e forks . According to th e t eam 's mech anics. they have clamps with vary ing offsets from 20 to 28 m m , which g et used depend ing on w hefher they are racing in sand or o n hard pack . Two ar eas of the bik e that differ s ignificant ly from t h e standard .r;'

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