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/126994
The u ltra-trick FZR400, Yamaha's newest sport bike. was made for the race track; it handles like a dream . Riding impression: 1988 Yamaha FlR400 Yamaha's little wonder By Farren Williams Photos by Bill Petro & Farren Williams T he introdu ction of the ultra- trick FZR400, which Yamaha bills as, "th e mos t exo tic midsized sp ort bike in the world," will spark a lot of interest am on g long-time pavement the motor in th e FZR400 has four. rat her than five valv es per cylinder. Compa ny engineers feel th e fivevalve des ig n works best on ly in cylinders larger tha n 175cc, th us th e '100's rela tively nar row bores are too small to tak e adva ntage of Yamaha 's un ique five-v alve co n fig ura tio n. O nce o n the ro ad . we d idn ' t m iss th e fifth valve a t a ll. T he rods. wrist p in s a nd ca ms hafts are m ach in ed from chrome moly steel to h elp the ,engine withsta nd th e 14.000 rp m red li ne, a nd a new cain cha in desi gn is reported ly lighter and stronger th an th e o rig ina l design used in the 1986 FZR400 . which was so ld in Japan. en th usias ts. Given th e poor sa les of 400cc mode ls in the pas t, ma ny mig ht wonder why Yamaha 6 wo u ld intro d uce a n ew. relatively ex pens ive, 400cc sport bike in 1988. T he FZR400 will retai l for $3999 ( 4099 for th e Cal ifornia mod el ). wh ich is' a bou t th e same pri ce as th e less-exo tic FZ600 a nd Suzuki's new 600cc Kat an a ). Yam ah a a d m i ts 4000. " is a lo t of money for a 400." Wi th t he FZR 400 . h owev er. Yamaha hopes to esta b lish th e 400cc mod el as a via ble en try into th e sport m arket by clearly selli ng q u ality. Yam aha claims the little FZ is. " the best sport bike available," (a matter of opinion ) an d boasts to buyers th at . "we haven 't comprom ised specs to red uce cost. " T hey certai n ly haven' t, Yamaha a llowed America n moto journal ists to spend a day aboard th e FLR400 (bo th th e California model a nd the 49-state mod el ) du ring a recent ridi ng sessio n a t Sha n nonvi lle Raceway in Shannonv ille, Ontario. Ca nada. Ever vone who rode the littl e machine ca rne a way from the .race track im pr essed. The FZR400 is powered by a 399cc•. in-l in e four-cylinder Ge nes is engine th a t pulls hard (as lon g as yo u 're in 'the right gear) a ll th e way to redline < 14.000 rp m. Like la rger Gen esis H faur -st ro ke pow e r p lan ts, t h e engi ne 's Iiq u id -cool ed , tran sver se cylinders are incl ined forwa rd 45°; the cylinders are fed by four 32m m downdraft Mikuni BDS32 co ns ta nt vacuum ca rbu reto rs. U n like th e larger Ge nesis powerpla nts in Yama ha 's FZ li ne. how ever . The instrument panel on the FZR400 (above) is simple and functional , ' (top speed reads 135 mph; redline on the tachometer reads 14,000 rpm) . The FZR400 boasts Yamaha's trick, Deltabox a luminum frame (below). A sta te-of-the-art compu ter co n trols both the TCI dual-coil ig n ition and th e el ectronic fuel pump, The Ca lifornia vers ion of th e FZR400 (the FZR400S ) wi ll be th e first production m otorcycle to offer what Yamaha ca ll s EXU P - a variabl e ex ha us t va lve syste m designed to co n tin ua lly a lter exhaust pipe tunin g to best su it diffe rent engine rpm. Yamaha clai ms th e EXUP system, wh en co mb ined with th e 4oo's other h igh-pe rf o rm an ce tuning. will . " de velo p th e sort o f power tha t wa s p reviousl y un ique to much bigger mo tors." According to Yamaha. th e system was ra ce-tested in J apan ea rly th is year by th ree-time World Cham pi on Kenn y Rob ert s who rode a n EXUP-equ ip ped 1987 YZR750. Yamaha claim s EXU P not o n ly will help th e California version of th e FZR400 meet th e sta te's stricter em issio n regu lat ions. but a lso wi ll boost lo w ia nd mid-range torque. resu ltin g in hi gher power o u tp ut. " For o nce ."· sai d Yama ha o fficials. "Ca liforn ia wi ll ge t a faster version than th e o the r 49 sta les." Ou r trac k , lim e p ro ved they 're not kidding j EXU P works. T he EX U P system --:- wh ich is sort o f lik e a four-stroke version of tIle p ow er va lve system o n Yamaha's two-str ok e mo tocross bik es - regula tes, " the flo w o f pos itive ,a nd negat ive pr essure wa ves to im prove , cyli nder sca vanging a t a ll engine speeds." accordi ng to Yamaha. , T he wedge-sha ped valve is located a t th e end of th e fou r exha ust p ipes w he re thev enter a fo u r- into-one ex ha us t coi lecto r. It is opera ted by a ste p less servo m ot or th ro ugh push l pu ll ca bles a nd is regula ted by th e ignit ion co m p u ter. Designed to be sensit ive to engi ne speed. th e EX UP valve is a lmost en tire ly closed a t lo w rpm a nd grad ua lly opens to perm it unrestricted exha us t flow at high rp m. Yamaha cla ims th e EXU P system results in smoo ther. quieter idl e, a 10 p ercent p o we r inc rease. a 30 percen t increa se in low- a nd midran ge to rq ue , a five p ercent decrea se in fuel co ns u m p tio n and a reduction in h ydroca rbon emissions o f betw een 20 and 30 per cent. Bo th FZR400 models sport Yamaha 's rig id . ligh tweigh t De ltabo x a l u m i n u m fram e. wh ich b oast s racin g techn ol ogy d eveloped b y former World Champions Roberts a n d Eddi e Law son. The bik e is suspe nded in front by a Ka yab a fo rk which boasts 38m m sta nc h io n tubes, T he rear Mo nocross su sp en sion co ntro ls a n aluminum swingarrn via a si ngle Kayaba shoc k with seven- way adjustable sp ring prel oad. T he 400 ha s massive di sc brakes to handle sto pping chores. Up front . th e FZR sports dual l l-inch floatin g . d iscs. a nd a 8.25-inc h disc shuts things down in ihe rear; The fu ll fa iring-equ ipped sportbike will co me sta n dard with Dunlop or Bridgstone low-p rofile rad ial tires ( 10170 R I7 53H o n th e front. 40160 R I8 64H o n th e rear ) mounted to holl o w cas t-a lu m in u m whee ls., On the race track ' The Ya maha FZR400 p acks p lenty o fp avem ent punch - just cli ck th e six -s peed tran smi ssion int o th e p roper gea r a nd foll ow up wit h it big twist of th ro tt le. U nder power. th e 400 accelerates h ard , a lmos t as h ard as its b ig brother . th e FZ600. If we had a cha nce to co m pa re th e two bikes side by side. we'd bet cold ha rd cas h that th e FZ400 would m at ch its bi gger brother beat for beat o n to p end at 135 mph (no. it won't cha llenge H onda 's CBR600 Hu rri cane).