Cycle News - Archive Issues - 1980's

just th a t. The Su zuki actua lly has a good, usable powerb and , a nd that's. something yo u don ' t a lways find on a hi gh -str u ng 80cc mot or. Ri gh t off th e botto m th e motor p ulls hard , a nd keeps o n pulling th rough th e midra ng e a ll the wa y to the u pper revs o f the top end. It has p lenty o f power to easi ly pull linger riders th ro ugh tig h t turns , a nd if the power falls off too i sha rp ly a couple of swipes on the clutch wi ll q uickl y bri ng th e revs up and get the mo tor h u m ming agai n. In order to han dl e the increased po -er Suzuki experimented with di fferent num bers of cl u tch p la tes before de ciding tha t t he sa me n u mb er of plates as last year wo uld do the job, but they did increase the size of th e clu tch . Whi le the transmission ratios remain the same, the sh ift shaft has been increased 2m m and the shift drum no w rides in ro ller bearin gs. Shifting wasnever a problem o n the RM80, even un der fu ll power a nd with oversized feet. . Frame g eome tr y is unchanged from last year, but the fra me is lighter b u t stro nger d ue to m o re r igid constructio n . Jus t like o n the bigger RMs oblo ng tub in g is used where th e rider stra ddles the ma chine , a nd th e left-rear fra me rai l is detachable for easier airbox a nd shock rem o val. .... v ...0 .o ..., u o -Suzuk i 's 1989 RM80 fea tures an all -new case- reed motor w ith a variabl e exhaus t valve, a f irst o n a m ini. Riding impression: 1989 Suzuki RM80K Big performance in a little package' valves block the iop of th e ex ha us t port at low rpm a nd heighten the po rt as the revs rise to a llow the gasses a qui ck er exit fr om th e cylinder into th e redesigned exhaust pi pe. At th e end o f th e pi pe 'is a n all-new, ova l si lence r wh ich mak es the '89 R M mu ch q uieter than p revious models. By Nate Rauba .It's been a little over 10 years SInce I sold my minicyc1e for a full -sized 125cc motocro sser, so when Suzuki invited the press o ut to Ascot Park for a special test session o n th eir 1989 RM 80 min imotocrosser I cou ldn' t wai t to get my h ands on it. H ' h d . . I av mg w.a t~ e rm rucyc es 24 o W. w from ba ~lc, in trod uc tory ra<;ers wit h a few lJ.1ch es of sus p~nslO n tra vel to th e. hi gh-tech machines of . tod a y that spon nearly the same amo unt o f travel as th eir fu ll -sized brothers, I kn ew that it wou ld be fun to relive a litt le bit of my youth on the RM80. And since I' m sho rt to beg in wi th, I knew th a t th e 33.I-inc h seat height wouldn 't mak e th in gs too cra m pe d whe n it came tim e to ride it o n th e track. Su zuki has a lways been a do minant force in m in icycle racing, partl y d ue to the fact that they su bcontract a sepa ra te firm , R &D Suzuki run by Rudy and Dean Dickenso n, to concent ra te on fielding to p-n o tch min icycle riders. Although R&D Suzuki isn' t the research and develo pment depart ment th at th e name implies, some o f the modifications ma de to th e ra ce bikes do aid develop ment in J a pa n. Last year 's R M80 wa s a p roven .winner, as dem onstrated by R &D Suzuki r ide r Buddy Ant un ez a t severa l of the major minicycle even ts, so in an a ttem p t to stay ah ead o f th e pack again this year th e '89 R M80 spor ts an a ll-new engine ne stled in basica lly the sa me pa ckage as th e previous model. One of t~e biggest cha nges ~he '89 mot or received was th e additio n o f Suzuki's Automatic Exh aust T im in g Contro l (AET C), making th e R M80 the first mini cycle to come stock wi th a ny kind o f varia ble exha us t valve. The all -new motor is fed by a M ikuni slingshot carburetor and has a w ide powerband. Even big riders can feel at home on t he RM80 due to its larg e size, and w ith over 10 in. of travel landing f rom jumps is no problem. Fitted to the end of the new pipe is an all-new silencer that makes it the quietest RM80 ever. It is the same va lve introduced on last year's R M l 2S a nd 2S0 wh ich varies th e heigh t o f th e exhaust port to match engine rpm. The sliding An a ll -ne w case reed-valv e intak e tr a ct is- fed by a 28m m Miku ni slingsho t carb uretor, the same lightweight, half- round slide with indexing ridge introduced o n the la rger RM s last year. The slide is m uch th inner than con ventional fla t slides and the shape reduces turb ulence to increase a ir flow in the carburetor throat . All o f the se changes were made to help increase ho rsepower at high . rpm whi le mainta ining qu ick response in th e lo w- and mid-ranges, and o ne ride on th e R M80 demon strates that a ll th e changes do exactly Suzuki's Full-Floater rear suspension is unchanged , a lt hough the shock now has both comp ressio n and rebound dampi ng; last year th ere was only o ne adj ustm en t. Up front the fork tu be diameter ha s been increa sed to 3Smm, a cha nge o f 2mm over las t year. Wh eel travel has been in creased by .4 in. a t bo th ends. Now I must admi t that I thought th at, in stoc k form, the suspension o n a minicycle wo u ld be way too so ft for a 160 lb. rider. Bu t I q ui ckly found that was n' t th e case. Wi th 10.8 in. of rea r wheel travel, the RM 80 is onl y 1.4 in. shy of the RM I2S's rear suspen sio n travel. So it is no wonder that the rear end was a lmos t as p Iu sh for. m e as th e R MI 2S' s, d espi te car ry i n g the increased weight. The only time th e rear end was inadeq uate was lan ding from the larger jumps on thetrack and the deep; G -out who ops. Bu t don' t forget that is for a larger rider. With a smaller and lighter person o n the mach ine th e rear en d p ro bably works fine, although since it worked so good for a heavier rider it may be a little sti ff for the ligh tweigh ts.

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