Cycle News - Archive Issues - 1980's

Last year Honda set some new design standards when they released the revamped CR250. Its low-boy exhaust pipe and resulting mass lowering and centralization of weight, alo ng with ergonomi cs that a llowed th e rider to eas ily clim b way up o n th e tank, were soon a ppearing on o the r bra nds on the Nat iona l circui t, a nd have even fo un d their wa y int o wider p roductio n thi s year. Alt hough the '88 CR250 set so me desig n standa rds, it s performance standa rds were less tha n what man y ex pec ted. Its , main faults were a pow erband tha t was difficu lt for th e averag e rider to use a nd a new Deltasha ped Pro-Link rear sus pens io n system th at o ften suffered from poor pe rfo rma nce du e to wimpy lin kage bolts that bent easi ly. It would be easy to di smi ss th e 1989 CR250 as nothing more th an a n updated '88 model. After a ll, exce p t for the a ll -new " in verted" forks a nd new grap h ics on th e '89 machine, they look identical. Bu t while th e '89 is basica lly a n u pdate over last year , it 's wh at's updated th at counts, a nd severa l vital areas received attention. The resu lt is a machine that is much d ifferent th an its predecessor, o ne th at H ond a hopes will o nce again set th e standa rd in the 250cc class. Makin' changes T he most obvious change made to the '89 CR250 is the switch to u psidedown or , as Honda says, inverted Sho wa cart ridge forks. No w, inve rted for ks have been arou nd a wh ile, most notabl y as standard eq uip me n t o n AT Ks, Cagi vas a nd KTMs, but '89 is th e fir st year that the J apan ese have ins ta lled the upside-down for ks o n their p roduction un its. On the H onda, fork tub e dia meter ha s been increased 2mm to 45m m, a nd the tubes sli de up into th e m a ssive 57m m s ta nc h io n tub es wh ich are held in pl ace by la rgediam eter tripl e cla mps. Th ere are 14 co m p ressio n damping adj us tme nts , made with a turn o f a screw a t th e bottom o f th e forks, but no adj us t. ments for rebound da m p ing. Protectin g th e forks are sano har dpl astic gua rds that wra p around th e fork tu bes so that they a re not on ly p rotected from roost bu t fro m lateral harm as well. With th e inve rte d d esign ther e a lso is n't a ny tube p rotrudin g below the axle to ca tch in deep berms or ruts. By now it sho u ld be com mon kn owl edge tha t th e inve rted fork design is co nsidera bly more rigid and th erefo re o ffe rs better fro nt -e n d sta bility and more precise co ntrol. And because the front end is mor e rigi d , it requires cha nges to th e fram e since gr eat er loads a re p laced on it, T he steeri ng head a nd downtu be have been stre ngthened to handle th e new loads , wi th othe r ar eas, o f th e (Above) Except for the inverted fork, the '89 CR250 looks identical to the '88 model. (Above right) A cutaway view of the Showa fork rests next to the working modeL (Below) Last year's CR250 had problems with the shock linkage bolts flexing, so this year the bolts have an increased diameter. 12 fri~e also stre ngthe ned. T rai l has been decreased .3 in. while th e ra ke rem ains th e sa me a t 62.5°, La st year H o nda revised th eir ProLink rear sus pe nsio n sys te m b y goi ng to a Del ta-sha ped design, but the stress of the new design easily The CR2SO feels light and can be easily controlled in the air. bent th e linkage bolts a nd hampered suspension perfor ma nce. T his year H onda addressed the p roblem by increasing th e diam eter o f all link age bo lts 2min. Other chassis cha nges in cl ude new d ie cast rear h u b, a redu cti on of four spo kes a t the rear wheel to sa ve weight, fewer bu t la rger dis c slo ts for , better hea t transfer, two less moun t- ing poi nts, resh a ped rear brake pedal with ratio cha nge for improved feel , 2mm wider foot pegs a nd the rear su bfra me , incl udi ng th e sea t, ha s been lowered 12m m for improved riding posit ion. , Nes tl ed with in the fram e, the mo to r has a lso undergo ne so me cha nges to not o n ly improve performa nce, but to improve d urabi lity as well, whi ch was o ne o f Honda 's ma in goals for 1989. ' New porting graces the cyIind er o f th e CR250. T he in ta ke boost port was deleted a nd cha nges made to the intake port fo r improved pow er a nd th ro ttl e resp o nse. Fuel reach es the ports through a n improved reed va lve that opens wid er. H o nda ' s P ower P ort (H P P ) exha ust valve size was inc reased to fit in a la rger exha ust port, a nd the sp ri ng th at reg ula tes the valves now opens 300 rp m earlier a t 6400 rpm for impro ved po wer. T he exha us t pi pe has a slig h t dimen sion cha nge a nd th e silencer is a litt le bit longer to brin g th e not e down below 100 decibe ls. Compressi on vo lu me has a lso been slig h tly reduced a nd th e head ga sket is thin ner a nd is no longer mad e of 'asbestos for healt h sa fety. T o improve d urabi lit y the piston now ha s a tin p lat ed pi ston-p in hole, and the taper o f the pin has been red uced for increased rigidity. In or der to rem a in du ra ble a nd han d le the increased power from the engi ne, th e ru bber damper in the cl u tch housin g has a new size a nd sha pe, heavier cl u tch sp rings are used a nd th e co unter sha ft collar is heat treat ed for increased oi l sea l life. With in the transmission the fifth gear ratio has been cha nged to bett er sui t motocro ss needs wit h less top spe ed. Flywheel weight has been redu ced for qu icker revs, a nd th e igni tion timing has been cha nged so that the power will come o n more gradua lly. The little changes made to the '89 CR went a long wa y. Performan ce has been sig nificantly improved over , last year's model. La st year th e mot o r had a powerband that favored th e aggressive rider. It had to be brough t up o n the pipe, into th e upper mid-range; befor e th e power reall y came o n since the re wasn ' t much lo w-end. Bu t thi s yea r th e po wer co mes o n much sooner th anks to a very stro ng low a nd midra nge. T he CR hits right o ff th e bottom , a nd hits with a u thor ity. Bu t it isn 't j ust a midrange mot or , th e pow er doesn 't sto p wh en the revs get higher. T he H onda just keeps on pulling in to the top-end a nd doesn 't begin to ta il o ff until just befor e redline. T he re is eno ugh lo w a nd midran ge power ' to ro ll into corne rs wit hou t downs hi ft ing. Open the th ro tt le a nd there's usuall y enough gru nt to pull you out, a nd if there isn 't a littl e slip of th e cl utc h will a lmos t a lways ge t the engine back into th e mea t o f the powerband. Even

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