Cycle News - Archive Issues - 1980's

The airbox is mounted in front of the gas tank. A chamber funnels clean air down the frame's backbone to a new 38mm TMX Mikuni carburetor. sw itching to diffe rent disc a nd pad mat erial s. White Power sus pe nsion compo- , nents soak up the jol ts fro nt and rear. T he fork is Wh ite Po wer 's 4054 u pside-do wn model, yielding 11.8 inc hes o f trave l, while the back is fitted w it h a s ing le p ig g yba ck reservo ir shock wi th ex ternal com press ion , re bo u nd da mp in g a nd pr eloa d adjus tments. R ea r whee l travel is 13 in ch es, T he shock ' is mou nt ed to the left side o f the sw ingarm and linkages are no t used. In stead, ATK wen t to th e mo re un corn p lex' route a n d mounted th e shock di rec tly to the frame a nd swi ngarrn. elimi na ting th e u se o f h igh-m a i nten an ce , , linkages. The 406 comes stock wi th a rather large pl astic gas tank , wh ich holds 2.7 g a llo ns . Pl a st ic is m ad e b y Acerb is, a nti the control levers, gri ps a nd thrott le assembly are made by Magu ra . AT K offe rs the 406 in two versions - mot ocro ss or o ff-road. T he only difference betwee n the two mod els is th e sus pe ns io n. T he o ff-road has much so fter front an d rea r suspension sett ings than th e mo tocros s version. An op tio na l spark arrester is a vai lab le for either mod els. When purchasing the 406, th e cus to mer can or der it in a variety of co lor co mbi na tio ns, to give it thei r o w n pe rsonal touch. It ca n be ordered wit h ei ther blu e-, whi te- or red-pai n ted, or nickl e-pl at ed silver fra mes, whi te or red gas tan ks, a nd a lmos t a ny colo r (incl udi ng zebra stripes) seat cove rs, a nd fen ders. Swing a leg over the ATK for th e first ti me a nd you'll immediatel y kn ow you're not o n top a j a panese mad e mot orcycle. It 's no t u nco mfo rtabl e, or a n ythi ng bad , it just feels di fferent. T he sea t is firm , the handl ebars have a n easy reach , a nd th e wh o le layou t is well ba lanced. The 406 has a left-sid e, easy-to-use kicksta rter a nd just a co u p le o f jab s brings th e Ro ta x motor to life, hot or co ld. It on ly takes a few seco nds for the engine to warm u p to wh ere you can turn o ff the choke. T he ATK isn't exactly quiet, th ough. The exha us t no te is a littl e lo uder th an most bik es of its size a nd th e cyli nd er' s .coo l i n ~ fin s rattle arou nd a bit, adding decib les. ' After dropping th e transmission into first gear a nd slo wly letting o u t th e clutch lever , th e 406 immediately jumps into ac tio n. Any slight twist o f th e throttle res u lts in ins ta nt response from the motor. And as you roll o n th e throttle, th e ATK begins p u lling hard a nd keeps pulli ng th at way until you run out of gears. Righ t At a claimed 213 pounds dry. the ATK 406 is the lightest moto rcycle in its class. The 399cc Rotax motor is air-cooled, and powerful. . ATK's Cha in Torque Elim inator alleviates rear end squat under heavy acceleration. New pads and disc are incorporated on the rear brake . from th e botto m o f th e rpm ra nge, th e ATK starts diggi ng for traction in smooth and co ntrolla ble fash io n. T he motor is impressive. Although th e 406 makes good power th ro ughout the po wer ba nd , it , h its th e hardest a t m idrange. Bu t th e transi tion fro m bo ttom -end to midra nge isn' t dra ma tic, ins tead, smoo th and bar el y noticabl e. O n tight, off-camber trai ls, where thro tt le co ntrol is cr itica l, you ca n just click in to the nex t hi ghest gear a nd let th e torquey Rotax mo tor idl e you th rough th e ugl y stuff. It has eno ugh botto m- end so tha t yo u won't have to use the clutch very often, a nd it has enoug h flywheel weight to keep th e mo tor fro m sta ll ing too eas ily. T he ATK has a longer shift th ro w than mos t of the j apanese dirt bik es, bu t it doesn ' t tak e too long gett ing used to it. T he transmissio n sh ifts smooth ly a nd p recisely a nd clu tch p ull is very light. T he cl u tch itself isn ' t gra bby nor does it seem to hea t u p ex tensively under hea vy use. T he 406 we rode o n ly had abo u t two hours worth o f break -in time befor e we got o u r hands on it, b ut th e suspens io n felt co m p letely sett led in. Bo th th e fron t for k a nd rear shock soa ked up the bum ps extreme ly well a nd had an o vera ll plu sh feeling. Even with the softer off-roa d suspen sion set-u p , we didn 't have problems with bottoming a t ei ther end , but for mot ocro ss use, th e stiffer suspension is be tter. We rode th e 406 with the mo tocross sus pe ns io n, as well. It definitely improved the ATK's feel on th e tra ck, and it a lso wo rked we ll riding at a fast clip o n the tra il. So me of th e rea l fast o ff-roa d riders m ig ht like the MX suspens io n on the 406. But the sof ter suspens io n is better for all-arou nd typ e riding. It wo n' t bea t ' you up. One of the most interesting features o n the 406 was the rear brak e. It was ex tremely touch y. At first it was reall y hard ge tt ing used to and we stalled the mot or many times because of its touch in ess. Plus, th ere's very little play with th e brak e ped al, whic h d idn 't hel p matters a wh ole lot. But th e mor e we rod e th e bike, the mo re we got used to th e po werfu l rear b rak e. But we never rea ll y got co m p lete ly com forta ble with th e rear binder before we ga ve the bi ke back to AT K, however , we could see how it co uld be a n adva ntage once you becom e more fam i l iar with i ts gra bby tenden cy. . Up front, th e di sc brake wasn 't nearly as to uch y as the back, though it had ple nty of pow er. It had a prog r essi ve feel a n d o ne -fi nger operation. T he 406 tu rn s quite well. Mu ch o f th is has to do withits ex tre me lyshort, 57-inc h wheelb ase. It div es in a nd o u t of th e tu rn s wi thou t much effo rt by th e rider, which is a bi g p lus for both motocross and o ff-road riders. T he Pirelli tir es stick fa irl y well. Desp it e its sho rt whee lbase, the ATK is sti ll very stable a t high spee ds in a straigh t line. We didn 't feel much head shake a nd th e back end tracked n icely over the whoops, rocks' and ru ts. P rob abl y th e most o uts ta ndi ng fea tu re o f the 406 is its weigh t. At a claimed 213 pounds dry, the AT K is by fa r th e li gh test motorcycle in its class. .You can easi ly flick the 406 a ll over the tra il wi thou t burning up A single White Power shock handles the bumps in the rear; no high-maintenancelinkages are used. .a lo t o f energy. It jumps we ll and predictab le, but doesn ' t feel busy or skitterish . We left our one- day ri ding sessio n with th e ATK 406 qui te impressed , but th e ATK does take a li ttl e getti ng used to. It 's no t the kind of mo torcycle you can just ho p o n a nd fly and feel com forta ble o n, especially if you' re used to j apan ese machines, like so many o f us a re. ' The ATK deserves respect and a good co u p le o f days of getti ng used to. It does every thing well , b u t it just feels differen t. If you wa nt th e 406 for a n off-ro ad bike, how ever, the adj us ti ng ,period shou ld n't take as long as it wi ll tak e on a mot ocro ss track. The bike feels prett y mu ch rig h t a t home on the trai l, but o n a mo tocross track, gi ve it a few days. Although th e Ca lifornia- based co m pa ny does no t o ffer a wri tten warranty for th e 406, a n AT K spokesm an says th at they will do wh atever it takes to keep its cus to mers ha ppy a nd roosting on the trai l, even if it sometimes means fix in g a brok en part for free. For those who are looking for a reasona lbly priced ($3980), reliable, easy- to- mai n tai n mot orcycle for o ff,road riding, or mot ocro ss, or even bo th , it' s go in g to be har d to beat th e AT K 406. It has a n exce llent a llarou nd motor, good sus pe nsion a nd handling, and , best o f a ll , it sho uld • last for a long, long ti me.

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