Cycle News - Archive Issues - 1980's

The growth on the Suzuki's cylinder head is the new exhaust-valve - sub-chamber. Linkages replace the shock strut o n Kawasaki 's Uni -Trak. Rear travel is 13.4 inches. exha ust-valve adj ustment knob locat ed o n the left side o f th e sub- cham ber. a llo wing th e p ow erb an d to be cha n ged to su it d ifferen t tracks and co nd ition s. On th e op pos ite sideof rh e su bcha m ber. there's a sma ll inspectio n win dow over the powerva lve mech a n ism . Unfort u na tely. the window is h idden behin d th e ex ha ust p ip e. which wraps aro und the rig h t side of th e motorcycle. Suzuki RM1 25G Eng ine type . . ... Liquid -cooled, reed-valve, two-stroke single Bore x stroke . ... 54.0x54.0mm Displacement ..... .. . •. 123cc Compression ratio B.9:1 Carburetor 34mm Mikuni Horsepower N/ A Torque N /A Starting system Primary kick Ignition Suzuki PEl Lubrication . . . . . . . . . . .. Premix Gear ratios Primary 60/19; 3 .157:1 Final 51 /12; 4 .250:1 6th 19/20; 0.950:1 5th . • . .. .. . . 20/19; 1 .052:1 4th 24/20; 1.200:1 3rd 23 /16; 1.437:1 2nd 22/13; 1 .692:1 1st 26 /13; 2.000:1 Frame Single downtube. split double cradle Rake . . . . . . . .. . . . . . . .. . • . 29 ° Trail 4 .3 in . Front suspension type .. . . Telescopic fork Fork tube diameter 43mm Front wheel travel 11 .8 in . Rear suspension type S ingleshock swingarm Rear wheel travel 12.4 in. Front brake 9 .4-in. disc Rear brake 4 .8-in. drum Front wheel 1 .60x21 in . Rear wheel 1.85x18 in. Claimed dry weight . . .. . 192.0 Ibs . Certified wet weight 210 Ibs . Overall length . . . . • . . . . 83.9 in . Overall width 33.7 in. Overall height 49.8 in. Wheelbase . . . . . . . . . . . . 56.9 in. Fuel capacity 1 .8 gal. Ground clearance 13.4 in . Seat height 36.4 in. Colors . . • .• .• •. •• • •. . . •Yellow Retail price ; $1999 Yamaha YZ1 255 Engine type . . . .. Liqu id -cooled. reed -valve, two-stroke single Bore x stroke .. . . 56 .0x50.0mm Displacement • . . .. . . . . . 123cc Compression ratio 10.5:1 Carburetor 34mm M ikuni Horsepower 33.4 bhp @ 11.000 rpm Torque 16.1 ft/ lbs. @ 10,000 rpm Starting system .. .. Primary kick Ignition •• • . . •• • . .. . . . . . .. COl Lubrication . . . . . . . . . . . . Premix Gear ratios Primary 60/18; 3 .333:1 Final 50 /13; 3.846:1 6th 22/21 ; 1 .047:1 5th 23 /20; 1 .150:1 4th 22 /17; 1 .294:1 3rd 26/17; 1 .533:1 2nd 28/15; 1 .866:1 1st 30 /13; 2 .307:1 Frame Single downtube, split double cradle Rake 27.5 ° A free-rolling eccentric cam on the Suzuki 's new Full Floater suspension rotates as the shock compresses, changing the leverage. Port layout is th e sa me for '86 but p ort timin g is slig h tl y d iffer en t. Su zu ki went to a flat -top. two -ri ng p iston. in stead o f a dome type. wit h a more co m pact com bustio n cha m ber; th e cha n ge is supposed to increase accele ra tio n a t high rpm by increasing the speed o f co m bus tion . And to g ive the RM more power th rough ou t the range a nd for qui cker th rottle respo nse. a lig ht er (yet stronge r) co n nectin g rod is used. Last year's co n necti ng rod weighed 4.62 OZ.; n ow it 's down to 4.47 oz. T he wa ter-cooling system still uses two separa te radia tor s mounted in fro nt o f a nd below the gas ta nk. T he (Con tin ued to pag e 22) Hond a CR125R Eng ine t y pe .. .. . Water-cooled. reed-valve, two-stroke single Bore x stroke 54.0x54.0mm D isplacement 123cc Compression ratio •. . . . . . 8.4:1 Carburetor 34mm Keihin Horsepower . . . .• • ... •• 33 .5 @ 11 .500 rpm Torque 15.5 IbAt @ 10.500 rpm Starting system . . . . Primary kick Ignition • . • . . . . . . . . . . . . . . . COl Lubrication . • • • . . . . . . .. Premix Primary drive . . . • •• Straight-cut gear Final drive #520 chain Gear ratios Primary . . .• . 64/20; 3 .200:1 Final •• •.. . . 51 /13; 3 .923:1 6th 23 /23; 1.000:1 5th 25 /22; 1.136:1 4th 26 /20; 1.300:1 3rd 28 /18; 1 .555:1 2nd 30 /16 ; 1.875:1 1st 28 /12; 2.333:1 Frame Single downtube, spl it double cradle Rake . • . . . . . . . . . . • . . . . . 26 .4° Trail . . . •• . .. . ...... .. . 4 .37 in. Front suspension type .. .. Telescopic fork Fork tube diameter 43mm Front wheel travel . • . . • . 11.8 in. Rear suspension type . .. . Singleshock swingarm Rear wheel travel . . . .. . • 12.2 in. Front brake 9.4-in. disc Rear brake 5.1 -in. drum Front wheel . • • •• • • 1 .60x21 in . Rear wheel 1.85x18 in. Claimed dry weight . . . • . 192.9 Ibs. Certified wet weight 207 Ibs . Overall length . • . . . . . .. 84.3 in. Overall width • . . . •• • •• • 32.5 in . Overall height . . . . . • • . . 48.4 in. Wheelbase 57.4 in. Fuel capacity . .... . • •. • 1.7 gal. Ground clearance .•. .. • 14.0 in. Seat height 36.7 in. Colors . .. . . . . . . . •. .. . . . . . Red Retail pr ice •. • . . .. . . . . . $1998 Kawasaki KX125E1 Tra il 4.53 in. Front suspension type . • . . Telescopic fork Fork tube diameter 43mm . Front wheel travel 12.0 in . Rear suspension type Singleshock swingarm Rear wheel travel 12.4 in. Front brake 8 .7-in. disc Rear brake 5 . 1-in . drum Front wheel " 1.60x21 in . 1.85x18 in. Rear wheel Claimed dry weight ... . . 191 .0 Ibs . Certified wet weight 217 Ibs . Overall length 84.1 in. Overall w idth 33 .5 in . Overall height 48.8 in . Wheelbase 57.1 in. Fuel capacity 2.0 gal. Ground clearance 13.8 in. Seat height 36 .8 in. Colors. . . . • . . . . . . . . . . .. White Retail price $2049 Eng ine type .. . . . Liquid-cooled. reed -valve, two-stroke single Bore x stroke 56.0x50.6mm Displacement 124cc Compression ratio 9 .35:1 Carburetor 35mm Mikuni Horsepower N/ A Torque N /A Ignition COl Lubrication. . . . . . . . . . .. Premix Primary drive Straight-cut gears Final drive #520 chain Gear ratios Primary . . . . • 63 /18; 3 .500:1 Final 47 /12; 3.916:1 6th 21 /22; 0 .954:1 5th 25 /24; 1 .041:1 4th . . • .. . . . . 26 /22; 1 .181 :1 3rd 28 /20; 1 .400:1 2nd • . . .. . . . 28 /16; 1 .750:1 1 st 30/13; 2.307:1 Frame . .. •. . • Single downtube. split double cradle Rake 27.5 ° Tra il Front suspension t ype 4 .6 in . Telescopic fork Fork tube diameter 43mm Front wheel travel . . ... • 11.8 in. Rear suspension type . . . . Singleshock swingarm Rear wheel travel 13.4 in. Front brake 8 .7-in. disc Rear brake 7.5-in . disc Front wheel 1.60x21 in. Rear wheel 1 .85x18 in. Claimed dry weight .• •.• 191 .0 Ibs . Certified wet weight 211 Ibs. Overall length . .. • • • • • • 84.6 in. Overall width •• . • .• • . . • 32.3 in. Overall height 46.9 in. Wheelbase 57.5 in. 2.0 gal. Fuel capacity Ground clearance 15.4 in. Seat height 37.0 in. Colors .. .. .. •• .. • . • " • • • Green Retail price $2099 I , ' , ' •t '. '

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