Cycle News - Archive Issues - 1980's

; I ~ :E ;2 >ell (/) 0 >0 l!') :I: e, 00 O'l Riding Steve Eklund's ABC-TV Su~elbik ers ATK Thump, thump By Kit Palmer P icture th is; yo u 're top ped ou t in fifth gear on p a vem ent doing a li ttle over 90 mph on a single-cylinder four-s troke. You come up to a tigh t turn and grab a handful of brakes; the , ...... ...... ...... .... v ..D. rear tire locks and slides out to one side with your feet resting '1' ff on t h e footpegs, tra i 109 a pu of bl ue smoke. You reach max- 8 v u v 0 (Above) Braking on Eklund 's Superbiker ATK was excellent. Even when the rear wheel lock ed up on the pavement, there was no chattering. Shorter-travel suspens ion. 1 8 -inc h wheels wit h Carli sle tires and stronger brakes changed the MX ATK int o Ekl u nd ' s Superbikers m ount. iumum speed fo r th e turn a n d let off on th e brak es, lean it over as far as yo u da re, reach th e apex, stra ig h ten up a nd g ra b a wrist fu ll of thrott le full y tuc ked in. You cli ck up a few gears a nd sta rt all over for th e next tu rn . T h en yo u run o ff th e p avem ent o n to smooth dirt a nd find yo urse lf with the bac k o f the bi ke pitche d sid eways, yo ur foot dra ggin g o n th e ground , maintain in g bal ance a t 50 mph in a turn . You're ca refu lly ap p lying and backing o ff th e throttle until you 're straigh tene d up aga in and sta rt looking for top gear on a straigh ta wa y. A few more turns , and yo u 'r e back on th e asphalt doin g 90. T hen th ere's a pause a nd th e next thi ng yo u know yo u ' re o n a m otacro ss tra ck, lauching 10 feet into the ai r over a jump on .th e same bike; yo u're reac h in g a spee d of 40 mph bu t afraid to go a ny faster down a stra ig h t in fested with whoops , bumps. potholes a nd ruts. You reach th e next . tu rn, lean it over in th e berm, and a huge wall o f dirt Ili es off th e rea r w hee l as yo u wick on th e throttle two different worlds on one kind of m o torcycle, a ll in th e same day. That 's wh at it's lik e ndmg the bike tha t Steve Eklund rode a t th e madefor-televisio n Superbikers combination pavem ent/dirt ra ce at Carlsbad International Raceway in Carlsbad, California, in November. Ek lund finishe d seven th over all at that ra ce, riding a n ATK four-stroke designed and built by H orst Leimer, an Austrian transpla nt doin g bu siness in Tustin , Ca lifornia. sell ing sus pe ns io n parts, swingarms an d com p lete mot orcycles. Consi dering th e co m pe titio n a t th e event, a seventh is very respectable. . T he A'TK visn't a new motorcycle, a nd a nyone wh o 's been aro un d th e motorcycle industry ha s probabl y seen one o n a motocross track, in a desert race o r in a n en d u ro . That' s wh at makes Lei me r reall y proud o f hi s crea tio n th e bike's versatility. It wa s to demons tra te just th at versatility that Leitne r gave m e the opportunity to ri de Eklund 's Superbikers ATK; wh en I had enough of sliding th e bik e aro u n d on th e str eet a nd d irt, Leimer turned the ma chine into a Iull -Iledged motocros ser in less than 30 minutes. Ekl und 's ATK wasn 't brand -new to start with; in fact, it wa s well-used by motacrosser Randy Rodriguez, who recently won th e Vet Expert cl ass a nd finished seventh in th e 500cc Pro class a t th e seven -race Trans-Cal motocross series held th rough o ut th e state o f California . The on ly modifications made to Rodri guez' bike for mot ocro ss (a nd a lso used for th e Superbikers event ) was a SupcrTra p pmcgap hone ex haus t pipe. For th e Superbikers race, ch an ges to th e bik e inc1 ud ed insta lla tio n o f wide, IS-in ch wh eels eq u ip pe d with Carlisle dirt tra ck tires; a mod ified , shorter White .... .. - . ' "1 " 1 ' . 1•• • , • • •• 1 Po wer rear shock and fork assem bly; and a sm all, wind-n;sistance-reducing front fender a nd WIder handlebars. That's it l Stock, th e ATK uses a 560cc lourstroke Rotax mo tor, A-Trak cha inten sioning system, a sing le Wh ite Power shock a nd invert ed 5045 forks, and a K&N a ir filter . Probably th e trickest set-up on the ATK, a s used by both Rodriguez and Eklund, is th e rear 'disc brak e. The d isc is mounted on th e co u nte rsha ft, o u tside o f th e co u ntershaft sproc ket, wh il e th e ca liper co n nects to th e en gine cases. According to Leimer , that br ak e location centra lizes th e overa ll weight o f th e bik~, and co m bined with th e A-Trak , elim ina tes rear-wh eel ch a ttering wh en braking on asphalt, which is a maj or problem encou ntered in th e Superbik ers race. O n Eklund 's bik e, th e caliper is sligh tl y larger th an th e o ne Rod riguez uses o n his motoc ro ss bik e, to imp ro ve braking power. One disadvantage with this braking design is that it puts twice as much strain on th e drive ch ain than a rear- hub-mounted system, sin ce the cha in now works to both drive the motorcycle and s low it down. A broken chain would leave the rider without a rear brake; however, Leimer sa id thrown cha ins have nev er been a problem o n th e A~K in th~ past. ~s luck would have it, Rodriguez did t~row a ch a in this da y on his practice blk~ on th e motocross. tra ck. An exce~sl vely w~rn out ch!1m was the cuiprrt, according to Leitner. I had no id ea what to expect when I fi! st hopped .a boa rd Eklund 's ~uperbiker s m~ chm e a n? had. nothm$ to compare It to. T he first thing I noti ced w~ s th at th e ~ a~d 1ebars w~re wa ~ too WIde for my liking . Co m bined with a low sea t height, th e bar s !!lade m e feel uncomfortable on th e bike wh en srtring in the pi ts. But as soon as I sta rte d gett in g o n th e gas , slidin g a ro und in th e turns, I forgot my un ease. The motor is incredibly p owerful, being rated a t over 60 horsepower, a nd feels much different th an other fo ur -strokes I' ve ridde n . T h is one is very fas t o n top a nd likes to be revved o u t; low -end power is oka y, but m idra nge o n up is fantastic an d throttle response is right o n th e money. . On the asphalt, the ATK doesn't feel lik e a stree t bike at a ll, nor does it feel much lik e a m otocrosser , eith er. It h as a mind of it s own ; turning th e ATK isn 't sim p le because it doesn 't want to be leaned over like a street or dual purpose bike. It took a lot of arm stren g th to keep th e front en d from wanting to stra ig h ten ing up and ca using th e whole bi ke to rise up too soon . After more and more practice ra cing through the turns, I began to ge t a feel fo r th e ATK a nd started ge tt ing th e hang of jamming th rough th e turn s qui ckl y. The best way I found through th e tight turns was to forget abo u t trying to lean it over a bunch ; just lean it ov er enoug h and let th e back en d do th e turning by letti ng it slide, using th e rear brake, , ••••J •••••• 1

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