Cycle News - Archive Issues - 1980's

Cycle News 1985 05 29

Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles

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~ a: w ::l; ..J '" rJ) 0 .... ~ O"l C'J 0 :I: e, ~ ro ~ The 2 4 9cc four-stroke engine produces ex cellent t orque without typical four-stroke hesitation. M otor and pipe are tucked in nice ly . . Test: RTL250 SO·trick, so few By Len Weed Trials enthusiasts have been waiting to buy a bike like the RTL250S ever since they first ' glimpsed the factory specials Honda prepared for former National Champion Marland Whaley and his teammates in 1975. Those 300s th ey rod e were su pe r slim, su pe r light, a n d boasted trials-tamed four-stroke 22 motors. But H onda never sold wh at Whaley co m pe ted o n, in stead, Ame rica n H onda p u lled o ut o f Na tional co m pet it ion a nd th e tria ls market af ter Wh aley (who gave them three stra ight cha m pio ns h ip s) mov ed to Montesa during th e 1978 season , Overseas, R ob Shepherd, who h ad posted th e first modern four-stroke victory in World competition in 1977, rema in ed in th e world 's top 10 through 1980. That same year, a yo un g Belgian named Eddy Lejeune, initially aboard a 200, became Honda 's top performer. Riding a 360 first introdu ced in 1978, Lejeune h as topped th e world for the past three years. This yea r he's attempting to make it four straight on a Pro-Link sing leshock Honda with a new 360cc mo tor. Am eri cans hav e had access to Honda tria ls mach ines since 1978 th rough sp ecralty dea lers, but th is is the first tim e th ey h ave th e opportu nity to p urchase wha t th e wo rl d team is competing on. All tea msters, exce p t Eddy Lejeune, are on th e RT L250. (Honda is al so developing a twostro ke tri al s machine.) , Ame rica n Honda, desp ite re-entry in the marke t by Yam aha, has n ot elected to ge t involv ed with trials again a t th is time. but this position might cha nge soo n , An y su ch decisio n would probabl y involve limited am ounts of bik es aimed a t th e serio us co m pe tition market. . C urre n tly th e new RTL250S is ava ila ble her e only from Bay Area Cycle Centre, a Los Angeles trials deale r that purchases the bikes on specia l order in J apan. This arra ngement p roduces a reta il p rice of $3400. Obviously, tha t price wo uld plummet if th e bik e ever were im ported by ' American Honda, . T he RTLs, unlike TLs, ar e not built by Honda but, rather , by HRC (H on da Racing Corporation ) - a sepa ra te non-profit R&D co m pany su bsidized by th e parent com pa n y a nd , to a degree, by Am erican Honda. HRC devel ops a nd builds limited q uantities of raci ng mach in ery suc h as road racers and Ilaurackers, which a re th en so ld through nati onal di stribu tor s. T he bik e used for this test, th e first to reac h America, wa s purch ased by Sco tt Annand, a So cal Ex pert compet itor. Annand previousl y o wned a T L R200. The RTL250 was first seen last fall wh en Ma zaya Yamamoto rode one in the final two world ro unds. Un kn own in world competition, he scored points in both even ts, including a six th. This performance, pi us the use of Pro-Link suspension, created immediate interest in th e machine. Despite th e sma ller displa cement, th e RTL250S seems at lea st-as power ful as th e original 300cc sho rt -stro ke ridden by Whaley. Those bikes were ideally su ited for slow riding over . loos e SoCal terrain. Another.version of the 300 - a stroker configuration gai ned favo r oversea s. This was th e uni t p referred by Shepherd . The 360cc monster mot or used by Lej eune was co nt in ua ll y modified before fin ally being replaced this yea r with a lighter, narrow er , sh ort er motor with a new gearbox. The RTL's 249cc powerplant is close to square with a 70 x 64.9 bore and stroke (the TL200 mea sures 65.5 x 57.8mm).. Compression is 8.2:1, and the motor achieves peak torque a t 4000 rpm - peak horsepower at 6000 rpm . One of th e amazing aspects about th e motor is it s compactness and narrown ess - the engine is roughly an inch narrower than the Yamaha TY350 powerplant. A 22mm ca rburetor is used. An external oil delivery system . using braided aircraft-type cable contributes to engine compactness. This system permits easy installation of an accessory oil cooler, a change favored by Lejeune for his big motor. Weight is trim med by using sa nd cast rnagne- siu m cases, aluminum motor mounts and silen cer. Th e motor is a n integr al part of the diamond o va l sp lit frame. The alumin u m skid pl ate, which wraps up and aro u nd th e contours of the motor, offers excellent protection. A stiff rubber cu shion is positioned between th e plate and th e motor to dampen im pact jolts to the cases. T he frame boasts a sea t height about a n in ch lo wer than the new Yamaha . The RTL is also the slimmest trials bike yet produced. Even th e fenders ar e slimmer than those found o n th e Yamaha which , in itself, is a triumph of lighter-lowerslimmer oriented. . The vented tank cover/seat piece is secured by two screws and one rubber strap. Two slots are found over the ca rb, just in front of the seat. Both sid es are also slo tted. At first glance, the gas tank appears inadequate, even for a thirstless four-stroke. A closer inspection revea ls the tank actually is co nto ured to fit down deeper into the fram e structu re th an first noticed: capacity is three liters (0.8 gallons). Most two-stroke tanks run one gallon or less. • The wheelbase is close to 52 inches, bu t th e steep front end geometry a llows excep tio na lly tight turning ca pa bilities. The steep front end a nd slim chassis make the RTL a delight for tight turns , but the rider must be alert. The Pro-Link suspension softened the harshest impacts. The appl ication of sin gle-shock technology to the slower speeds of trials produces exceptionally plush riding. Experimenting can no doubt fine tune the shock to produce the rebound effect preferred for bounding up and over taller, steeper -steps. On lower steps and rock piles, . the rear wheel feels like it's floating. The leading-axle forks are aircapped, but the Pro-Link rear suspension is the main attraction. A massive aluminum alloy swingarm is connected to a Showa shock which

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