Cycle News - Archive Issues - 1990's

especially to its wa ter-cool ed , 124cc two-stroke motor. In quest of even more power off the bottom and a fatter midrange, Kawasaki returned to th e sq u are bore-and-stroke 54x54.5mm con fig uratio n, as co m pared to th e 56x50.5mm configuration of the '91 model. Then, a flat-top piston, wh ich Ka wasak i cl a ims runs co ole r an d reduces fla me len g th fo r better combustion efficie ncy , was inserted. Th e KIPS exh a u st power-va lve system was signi fica ntly redesigned to aid all-around engine performan ce, and a bigger 36mm (formerly 35m m ) Keihin carburetor is used. The airbox and filter eleme nt ar e al so larger. The motor's cooling system wa s also modified by using larger radiators from the 1991 KX250 model. As a result, cooling capacity is in creased by nearly 10%. In the transmission, th e clutch ha s been modified to improve durability and lighten pull at the lever. Even the perimeter frame got a lot of attention, mostly in the form of strengthening. Kawasaki says th ey were abl e to increase rigidity without addi ng extra weight by strategica lly adding more gusseting around th e steering head and decreasin g/increasing wall thi ckness in other areas. Plus, the area around th e top rear shock mount has been beefed up consi derably, and there's an additio na l cross pipe behind the engine cases. T he KX features floating disc brak e rotors at both ends. Kaw asaki claims the floating-type design offers better pad/di sc alignm ent under severe riding condit ions, especiall y up front when the fork flexes u nde r excessive side loads. Suspens ion-wise, there are very few change s. The inverted Kayaba for lt is basicall y the same, wh ile th e single Kayaba shock features a 15mm longer body (t h o u g h wh ee l travel is u nc hanged), a nd a larger remo te reservoir, claimed to hold 10%mor e oil. O th er no table changes incl ude a longer sea t, na rro wer m id sect ion, radiator shrouds that now cover the ent ire reshaped gas tank with the same capacity, and a new pulley-type th ro ttle design to reduce friction for lig h ter actio n . . The KX has a claimed dry weight of 191 pounds . Honda CRl25 Beyond its obvio usly new and striking fluorescent red arid white color scheme, the CR I25 features a number of sub tle internal changes. Like th e Yamah a and Kawasaki, the Honda 's liq u id-coo led, 124cc twostroke motor features a flat -to p , rather tha n do me, p iston, mainly to increase co m p re ssi o n i n th e co m b us tio n chamber, according to Honda. Not only was compression bumped up, but the Keihin 36m m carburetor, reedvalve an d ex ha us t por t - wh ich is regu lated by H onda's Po wer Po rt exhaus t-va lve system - were also mod ified to help achi eve a clai med gai n of o ne hors epower o ver the '9 1 model. The cranksh aft was also heattreated fo r i nc reased r igid ity and du rability. Besides the new grapics, perhaps the mos t obvio us change is the all-ne w, 43m m inverted Showa triple-tapered fro nt fork. The tapered secti on of th e fork tubes, that can be seen between the tri p le clam ps , is desig n ed to actua lly ind uce for k flex since many riders feel tha t the inverted for k design is, in fact, too rigid, resulting in a har sh feeling th rough the handlebar s. The trip le-taper is designed to alle via te th at harsh feeling. Not so obv ious is tha t th e front wheel travel has been increased sligh tly and the damping and spri ng rat es revised. For the first time the CR's fork has both l7-way com pressio n a nd rebound damping adj us tme nts. Like the fork , revisions were also lo-< V ..D. S V > o Z Although the Yamaha has excellent suspension, it's held back by its motor. Though better than last year's mill, it lacks a strong punch off the bottom and on top. carburetor and cra n kcase, is fitt ed in an effort to increase midrange power and en ha nce thrott le response. Pa st RMI25s have been cri ticized for the lack of top-end power, and Suzuki addr essed th e problem by design ing an a ll- ne w ex ha ust pipe th at features fewer curves. Larger-diameter and stre ngthe ned primary drive on the cra nksha ft and primary driven gea rs beh in d the clutch have been added to increase cra nk inert ia a nd smoo th engi ne power del ivery. The clutch received bigger p lates coa ted with a new ma terial for easi er o pera ti on a nd feel , p lu s incr ea sed du ra bil i ty. A works-li ke ma gnesium clut ch cover was ad ded to red uce weight. An all-new frame feat u res a lar gediameter , sq uare cross-sectio n tube backbone. Squar e cross -sectio n down tubes con nec t i t to the swingarm pivo t, wh ich has a larger shaf t. Su zuki claims Yamaha YZl25-Dl Engine type .. . Liquid-cooled, casereed, two-stroke, single 56.0x50.7mm Bore x stroke Displacement 124cc Compression ratio 8.7-10.6:I Carburetor Mikun i 35mm Staning system Primary kick Ignition COl Lubrication Premix Transmission Six-speed Primary drive 60/19 51/ 13 Fina l drive Frame High tensile steel, semi double cradle, aluminum rear sub-frame . Fron t suspens ion Kayaba telescopi c inverted fork Front wheel travel 12.2 in. Rear suspension Monocross, Kayaba sing le shock, swingar m Rear wheel travel 12.8 in. Front brake 9.8 in. disc Rear brake 8.8 in. disc Front tire Dun lop K-490 Rear tire Dunl op K·695Claimed dry.weight 201 lbs. Overall length 85.3 in . Overall width 33.5 in. Overall height 48.3 in. Wheelbase : 57.9 in. Fuel capacity 2.1 gal. Ground clearance 14.0 in. 37.1 in. Seat height. Colors White w/magenta Retail price _ $3599 that overall frame rigidi ty has been increased by 25%. T here are al so new front and rear Sh owa suspensio n com ponen ts. The inver ted fro n t fork has stronger inner tubes, o n e-piece fork sea l collar, str onger oil and dust seals, revised damping rates an d la rge r p lasti c protectors. A lar ger piston and cyli nder are included to gi ve the rea r shoc k performed to the damping ra tes in the rear Showa shoc k. The CR 's fram e geo metry is sl ig htly modified , wh ich is co mbined wi th a sho rter whee lbase, to quicken steering Lighter wheel assem blies he lp reduce weig h t, wh ich Ho nda claim s to be 192 pounds. There is also an all-new fro nt brake system with redesigned caliper, disc , master cylinder and brake lever. Su zu k i R M I 25 Aside from the hate-it-or-love-it yellow/whi te/purp le/ red coior combination, the '92 R M 125 appears exactly the same as last year's model. But there are man y cha nges h idd en undern eat h the new pain t. T he co m p lete crankcase ha s been redesigned to provide a straig h ter and smoo ther intake tract, and a sho rte r intake manifold, between th e Mikuni 7

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