Cycle News - Archive Issues - 2000's

1975 Suzuki XR14 _ Newbold finished second on his fi rst visit to Spa - some achievement, though sadly it was the last time he wou ld race t h e XR 14 . Sheene and Suzuki had some c o ns o l a tio n , though: Barry's new lap record set in the race at 135.75 mph still stands today as the fastest -ever lap in any Grand Prix race - anytime, anyplace. Suzu k i ' s response to the failure coul dn't be fau lted. Just two weeks lat er , at t he Swedish GP at Anderstorp, Shee ne qualified on pol e with a n ew one-p iece ' p rimary shaft made from a solid billet fitted to his engine which had been flown in from Japan, going on to blitz the field in the race , which he won easily, though Lansivuori crashed again. The Finn made up for th.is by finis hing se cond on home ground at Im atra the following week , where Sheene reti red with his engine m isfiring because of being set up too rich . In the final race of the season at Brno, it was Tepi's turn to take pole ahead of Sheene, but in the race the Suzuki ri ders had to grapple wi th the extra weight an d bulk of a nine-gall on fuel lo ad, necessitated by the o rganizers' decision. t o run an extra -long 115-mile race on the fas t public roads circuit. To make matters worse, the FIM j ury banned the use of slick tires at 8 a.m. on rac e morning after ear ly rain - even though the sun was shin ing brigh t ly l a t er , hours before the race. In spite of this handicap , Sheene battled with Read (whose four -stroke MV needed less fuel) for the lea d in the first few laps, before ret iring with a rumbling engine . Lansivuori took up the cha llenge, but retired on the last lap with a broken c lutch , and To racca dropped out early on. It was a low key fina le to Suzuki's breakthrough seaso n. La nsivuori finished fourth in the Wo rld Championship and Sheene was si xt h , with Suzuki third in the ma nufacturers series . It was a season , however, which had laid the ground in fine style for the advent of the RG5 00 Mark 1 a few months later, a bike tha t was in every way a close replica of the 1975 XR14 works racer -~a s well as for Suzuki's shock decision to~ ~thdraw fro m rae- _ -- 32 MAY 3 1 ,2000 • --o -- U - c _ I _u - -' The Suzuki could not have bee n b uilt more schizophrenic. The engine was revolutionary w ith over 100 horsepower at the rear whe e l an d u nmat c h e d top speeds, but the f ram e might have been more akin to a riding lawnmower than a racing motorcycle. It took guts to ride this b ike at rac e speeds. ing as a factory team, i n st e a d entrusting thei r official Grand Prix race operation to Heron Suzuki. Sheene dominated the 1976 World Championship with a new 54 x 54 mm version of the XR 14 , known as the RG500A thanks to th e A -shaped sub -frame behind the seat, and fitted with seven-port barrels instead of the five-port cylinders of the ' 75 XR14s , whic h Heron conti nued t o enter for the ir second -string riders. These were still good enough to propel Sheene's John-Boy teammates Williams (Spa) and Newbold ( Brno) to Grand Prix victory, as Suzuki won their fi r st 500cc riders and ma nufacturers GP titles . Though the RG350 wh ich Ogbourne d rew up but never built, and the RG750 which did apparently run on the dyno in prototype form, and would have blitzed the TZ750 if Suzuki and the tire companies had found a wa y of putting more than 150 hp to the ground, were sp in -off projects that did not materialize, the 135 hp 65 2cc XR23 version built for the Imola and Ricard 200 -milers , on which Sheene won the 1977 Bri tish Superbike title, did. That 1975 Assen victory was the first of m an y for the square-four Suzuki, and a watershed moment in 5 0 0 c c Grand Prix h i st o r y . Mission accomplished . Rid ing the RG = Really Good The mean-looking quartet of smoke-spitting sti ngers rasped their sharp, trademark c rackle across the Montl hery p addock , accompanied by th e dist inctive rattle of the XR 14 's r o t a r y valves as Nige l Everett dropped the clutch , and the Sheene Suzuki bu rst swiftly into song . As redolent of racing in the 1970s as an open megaphone mounted on a Manx Norton is of the p revious deca de, j ust watch ing _a ~ (L!!ste n i n g , to the sou nd ---n ..... as he warme d it up provided a st ir ring trip down me mory l an e, to t he final year that Grand Prix bikes rac ed without silencers: 1975. it wa s also the y e ar thatthls ve ry b i k e deliv ered Suzuki it s first -ever 500 cc GP win. Owning an ex -work s Ja panese GP racer is the dr eam of many , but the goo d fortune of j ust a few. But in thi s li fe , y ou m ak e yo u r own lu c k , an d B ri t i sh en t h us ias t Chr is Wilso n's sup erb co ll ec tion of fa ct ory 500 c c tw o-strokes h as been built u p over t h e past f e w y ea rs t h a nk s t o h is determ ina tio n to p re se rve th e ofte n uncon sid ered GP heritage of th e '70s and '8 0s post-Classic era . "T he root s of the wonderful t ech nol ogy w e see in Grand Prix rac ing t oda y are often taken fo r granted : says Wilson. " A nd , in seeking to preserv e th em , it's been surprisin g how many wonderful b ikes have turned up in a very sorry state, having been just slung in a corner and forgotten. My overriding philosophy is to restore my b ikes to o r i g i n al , authenti c , track worthy condition, then get them ridden in someth ing approaching anger b y peop le who know how, That's why you 're here at Montlhery, stand ing in for Mr. Sheene!" BUT WHILE THE XR'14'S POTENT SQUARE-FOUR POWERPLANT HASTENEO THE ENO OF THE FOURSTROKE GP ERA, ITS CHASSIS WAS FIRMLY ROOTED IN THE PAST Sorry , on l y a pa le imitation , I'm afraid - but if you were one of the fortun ate thousands at th e Ass en Centennial meeting in May ' 9 8, you 'll have seen Shee ne himself riding the same blue -an d-white machine, aboard which he'd opened his 500cc GP v ictory ro ster 23 years before . And on the very same track. It's a bike of initially indeterminate h eritage and one t hat Wils on had acquired as a box of not very large parts some time ago , on ly to discover from the Hero n race records held by George Bea l e that it was inde ed Sheene 's 19 75 machine and thus his Dutch GP winner - with chassis G561026. She ene himself was skeptical, beli ev ing no 1975 works b ikes had survi ved the c ru sher , but he wou ld later confirm it when he rode the bike at As sen . It was indeed h is and he even signed the top of the fue l tank to confirm th is. He sti ll described it as a ' h eap of junk ' , though , after bein g bl own off in the Centennial "race" by Mamola and Hartog on m uch later Suzukis with u p to 40 percent more power . Once a racer, always a racer. Still, by the standa rds of 1975, the XR14 Suzuki opened a window on a brave new wo rld : j ust five years after See ley G50-mounted privateers had been regula r visitors to GP rostrums, the XR 14 was the first 500cc GP ra cer to deliver over 100 bhp at th ~ "'---"--. . '~ ._~-- -s-_-- ---.---" _- ' rear wheel ( 10 1 bh p at 11 ,2 00 rpm on the Ev erett dy no , runn in g on 3 0: 1 Avgas j Sil ko le ne p rem i x ) - t wice as mu ch as the Briti sh sing les , resulting in a 175 mph to p speed that was 3 5 mph fa st er than they co uld m ana ge. Th ough other XR 14 s used l i ght er mag nesi u m c ran kcase s , pro bl em s with the po rosit y of the se pe rsua ded Sheene to in si st th at his b ike us ed heavier aluminum on es like the ones fitt ed here , with four separate cranks on the 56 x 5 0.5 mm sq u are - fou r rotary -v alve con figu ration , individual ly geared to a primary p inion under th e cy linders. Th ese wer e ar rang ed in a fl at square, angled sli ght ly forward: the l a t er , stepped -c ylinder , twin crank version of the RG500 was only adopt ed later (from the 652cc XR23 onwards), to provide space for a cassette transmission, with a raised id ler gear. A pair of 34mm Mikuni m agnesium - bodied carbs is mounted on either side to feed the rotary va lves splined to the cranks , and th e fiveport cylinders (four transfers, plus a booster port aligned with a window in the piston ski rt) have steel li ners chrome bores were still in the experimental stage back in 1975, and kept flaking off, recalls Ogbo u rne , so Sheene rejected them for h is bike, There's a single bridged exhaust po rt that's responsible for the harsh crack to the Suzuki's engine note, whereas Yamaha's rounder porting of the era produced a much softer, muted sound. But while the XR14's potent squa refour powerplant hastened the end of the four -stroke GP era, its chassis was firmly rooted in the past, with a relatively flimsy twin -lo op tub ular steel frame equipped with twin shocks ( Hagons on this restored bike, Kayabas in the era) and 35mm Kayaba forks , with adjustment restricted to changing the oil or altering the air-damping pres sure . Head angle i s a kicked -out 29 degrees; trail an equally humungous 12 5 m m , though at 1395 mm the wheelbase is quite compact, and the 297 -pound half-dry weight m ore than respectable, thanks in part to the profusion of titanium fasteners, each with their heads patiently scalloped out. Sheene 's preferred Campagnolo cast wheels are fitted with skinny 18in ch Avon tires kindly do nated by the British firm, who were happy to let Wilson retain the Michelin stickers on the bike's fairing , which is exactly as Sheene used to race it . It's an authentic restoratio n, which is a cred it to Everett's ha ndiwork. Which is why when Wi lson asked me to join Jean- Fra nco is Balde aboard the Wilson Kawasaki KR500, and Marc Fontan on Chris's wor ks '83" Yamaha, to ride the bike in a quartet of demos in front of 30,000 spectators at France's ann ual Coupes Moto Leg en de m eetin g at Montlhery, I di dn't nee d asking twice. I do have a selfinterestedly cautious approac h to track tes ti ng pe riod t wo -strokes, on _ - - _. - -.--""""'--'

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