Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/127183
The long-awaited RMX250 has all the goodies an off-road rider needs. such as a wide-ratio transmission. a heavy flywheel. a big gas tank. an odometer. brake guards. lights and more. For $3899. it better have. When Suzuki decided to re-enter the off-road market after an eight-year absence, the company had an all-or-nothing attitude in designing its first new enduro/off-road model since the demise of the . I b ki P E I 75. In ItS p unge ac mt~ th e o ff-road market , Suzuki wanted to make waves rather th an ri pples and wh a t Suzuki en gineers ca me up with is th e longa wai ted 1989 RMX250. The in ception of the RMX starte d becomin g a rea li ty two yea rs ago when Suzuki hired ISDE gold medal- 1St Cha rles Halcomb to help design an "off-roa d enduro-type prod uc uon mot orcycle." And LO hel p Hal comb wi th th e project, Na tio na l end u ro co m pet ito rs Randy H a wk in s and Dave Bert ram ga ve th eir impu t by co m petin g th e ent ire 1988 AMA Natio n a l C ham p ions hip Enduro Ser ies o n wh at Suzu ki ca lled RMXmodi fied RM250Js. Fo llowing th e long season H awkins did Suzuki o ne better by ca p turi ng th e number one p late, gi ving th e co m pany its first ever Nationa l Enduro Champion sh ip titl e. Pl u s, a ll th ree ri ders co m pe ted in the 1988 Intern a tional Six Days Enduro in Fran ce an d a ll three riders ea rned go ld m edal s. Their exper ience throughou t th e year was used in th e developem en t o f th e p roducti on '89 RMX. The RMX is based o n th e 1989 RM 250K rnot ocrosser . It uses th e same two-stroke, wat er-cool ed , casereed induction , 249.6cc mOLOr" a nd fra me construction/geome try as th e RM m o tocr o sser. H ow ev er , th e m o tor h a s in co rpo ra ted severa l modifications to make it better su ited for o ff-ro ad ridi n g and to meet the stri ct 82 db . fed er a l EP A n oise regulat ion, whi ch all manufacturers must pass before th ey ca n legally o ffer a n "o ff-ro ad " model in th e U.S.. Performa nce-wise, th e on ly difference between the RMX an d th e RM mOLOr is th at the RMX is fitted with a two-ri ng p iston (ra ther th an a o neri n g p isto n used in th e RM ), a hea vier flywheel an d a wide-ra tio transmission. T h e advantage of th e two -ring p iston is that it increases co m pressio n, resu lting in better low-en d performance. Bu t for th ose wh o wa nt more revs, you ca n use j us t o ne ring. T he cyli nder and cyli nder head a re th e same as the RM's. The cra n ksh a ft. how ever, is slig htly lo n ger on th e left' side to acco m moda te a larger a nd hea vier flywheel with b ui lt-i n Iig h tin g coi Is. Carb u retion is hand led by a 38mm fla t-slide T l\l X Slingshot Mi kuni. Bu t to ma ke the RMX quie t enough LO pass the EPA so und test, Suz u ki h ad no cho ice but to m ake many horsepo wer-robbing modifi cations to the motor. There 's a throttle sto p in th e carb uretor LO keep the sli de from o pe ning a ll the wa y; th ere's another stop in th e exh aust power-valve, prevent in g th e valves fro m ope n ing a ll th e wa y; th ere's a restricti ve co ver over th e airbox ' air inta ke o pen ing, a nd th ere's a monsterous steel si lencer/spark arre ster a ttac hed LO a q ui eter double-wa ll , exha ust p ipe, which is mounted low in th e fram e. . The RMX has a five-speed widerati o tra nsm issio n designed LO m ake th e RMX m ore versatile on th e tra il. Ever y gear exce p t for sec o n d is cha n ged. Below is a cha rt showing th e d ifferent gear -ra tios between the RMX and th e RM . The chrome-moly stee l tu bi n g frame and chassis are nea rl y id entical to th e R M's. They both have an a lu m in u m detach ab le left-side subframe sect ion, bu t th e RMX has bo lto n ro ck 'g u a rd s to p ro tec t the cran kcases. Stopping p ow er is ha ndled by fro nt and rea r dis c bra kes, but un li ke th e RM, the RMX has a n a lu mi n um alloy rear dis c cover a nd a p las tic cove r guarding th e front d isc bra ke asse m bly. Suspension is si mi la r LO th e RM's. The RMX has a n inverted Kavaba fork wi th 2 1-way adjus ta ble co m pressio n /rebound da m p in g setti ngs and the latest Fu ll Floa ter rear sus p ens io n design. T h e rear Kayab a shoc k has 18-way co m p ression an d 21-way adj usta b le rebound damping sett ings. H owever, th ere ar e so me differences betw een th e RMX sus pe nsion and th e RM sus pe ns io n. The rear shock on th e RMX ha s li ghte r low-speed co m p ressi o n damping an d th e front fork has a: different pi ston design than th e RM. Plus , g re ase Ii tt in g s hav e b een inst all ed a t a ll rea r sus pens io n lin kage pivot points. A lot of attention went into detailin g with th e o ff-ro ad rider in mind. The RMX has a larger 2.9 gallon gas