Cycle News - Archive Issues - 2000's

the extra capacity initially delivered too much power for the chassis and skinny rear tires of the period to handle, so it was detuned to a less extreme I35 bhp at 10,BOO rpm - still substantially more powerful than any other race bike of the era and quite a bit more potent than the I 14bhp XRI4. The liquid-cooled 62x54mm XR23 engine also differed from previous 500cc designs in having just two crankshafts, one for each pair of cylinders, rather than four separate ones, each geared to a primary gear beneath them, as before. Twin 36mm magnesium-bodied Mikuni VM carburetors were mounted on either side of the engine to feed the rotary valves splined to each end of the cranks. The engine had sevenport cylinders - six transfers and a single loop scavenge port - featuring a single bridged exhaust port that was responsible for the harsh crack to the Suzuki's ename nate, COl. . . . 110 ~~,.,l say, a YImaha of the which produCed. much softer, muted sound, Ignltlan was via a Nipponclenso COl, with the cassettetype six-speed gearbox mated to a multiplate dry dutch. ThIs ultra powwflouse was paradoxically only slightly beefed-up venion tvmsy.Iooking ... the XR 14, with the addition of bracing struts for the front cylinder-head mounts and fitted with a slightly thicker 37mm Kayaba nitrogen-charged air-damped telescopic fork. A fabricated twin-shock aluminum swingarm - rather than steel - was employed for the first time, increasing rigidity by 50 without any weight penalty. Rear suspension was provided by a pair of extremely costly, nitrogen-charged "Golden Shocks" - expensive not because they were manufactured by Kayaba in precious metal, but because their aluminum bodies were handmade from solid billets one of the Oulton Park Match Race legs, and then sprayed gold! These had no Hennen finished top scorer for an upset overall victory. Suzuki left the four 652cc springs, were exclusively air-damped, and bikes in Britain for them to be raced in the for the first time introduced the complexiMCN Superbike series, where there were ties of modern suspension setup to the no homologation issues, just a straight racing arena by being fully adjustable for 750cc top limit, and Suzuki was rewarded compression and rebound damping as well with the series title for Sheene, with four as (via the chosen gas pressure) for prerace wins, and two more for Hennen en load. The same pair of 295mm floating route to third place in the points table, steel discs with twin-piston Tokico calipers with Parrish sixth. as on the 500 were mounted up front with An abortive Continental outing to Paul a single 240mm ventilated rear, providing Ricard for the Moto-Journal 200 was barely adequate stopping power in view of rewarded by a series of improbabilities the XR23's astounding performance. It that prevented any of the three from finbecame the first modern racer from any ishing at a track whose long front Mistrale firm to break the 300kph (IB6-mph) mark straight would have appeared tailor-made when it was trapped at 303 kph (I BB mph) for the Suzuki rocketships, but Sheene at Fuji Speedway in testing. made up for that with victory on the XR23 Suzuki's view of the XR23 as a rolling at Chimay on his favorite public roads cirtest bed for its 500 GP program was cuit, averaging 127 mph to win the GP des underlined by the fact that they made no Fronlleres. It was aItoged lei a saIlsfaaory attempt ta homologate It far World • CI1ImpIoqIIIIp,~7iQ.~~~,.# at the yW\i~_I4f.ibM ~. spurious attempt to c:onstnJCt 25 stnlet Ina year of the fadory* Ilt-ntw )(JU1 versions, as Yamaha had 500cc contender - complete with the arne pretended ta da in stepped cylinder format and cassette gearorder ta make the box that had been tried and tested sueTZ700/750 eliglcessfully In the 6S2cc racer. b1e. Instead. four For 1918. ~ ptoelucltd an upnIIId __ion. the XJU3A, . " 1IIIIOll. system the 1979 season. the ex-Hennen bike was returned to the UK by Hartog, then shipped to Malaysian Suzuki importer Goans Hoe, where it was raced for a couple of years before being acquired by peripatetic German privateer Gerhard Vogt. After that, the XR23B eventually found its W&'I bKk to BritaIn. where It stayed unused In a private collection till August involving a pullrod rather than pushrod format, then-experimental chrome-bore Nikasil cylinders rather than the cast-iron liners used hitherto, and improved twinfloat Mikuni carbs (now with plastic venturis) aimed at countering fuel surge under the vivid acceleration the bikes were capable of. Top speed was now 191 mph, though power and weight were unchanged. Once again, the bikes were raced pre- 1999, when it was acquired in by British enthusiast Chris Wilson, whose superb array of works two-stroke racers has been built up over the past decade as a testament to the often unconsidered GP heritage of the '70s and 'BOs post-Classic era. The man who looks after the Wilson collection of bikes and keeps them in authentic, track-worthy condition is Nigel Everett, whose Racing Restorations company did just that to the XR23B, in which with a l'1IYIMd-ehRich operating bikes were built and hastily air-freighted to Britain just five days before the April 1977 Transatlantic Match Races - one each for Texaco Heron teamsters Sheene and Steve Parrish (riding for the British squad), plus a spare for Bazza and a fourth bike for American Pat Hennen, now established in the Suzuki works team run by British importers Heron for the factory and first of the fleet of U.S. riders to make their mark in 500cc GP racing over the next quartercentury. Indeed, although it was Sheene who gave the XR23 its debut race win in dominantly in the UK, with Hennen once again finishing top overall points scorer in the Transatlantic Match Races, winning three of the six races, with Sheene winning one. Hennen had apparently learned the setup tricks of the Golden Shocks better than Sheene, one reason for his success alongside his equal mastery of the wheelstanding rodeo racer's rush of power. But it was Sheene who retained his MCN Superbike series crown with six race victories, after the American sadly suffered his horrific career-ending injuries in the Isle of Man TT that year. Hennen's forced retirement meant that there was a spare XR23A going, and this was entrusted to Dutch white knight Wil Hartog for the rest of 197B. culminating with him beating Sheene to win the final round of the MCN Superbike series at Brands. After that, Hartoa was given the bike, painted in his uadeirnaJrit Rimersma colors, for the whole CYCLE NEWS • JULY 6,2005 57

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