Cycle News - Archive Issues - 1970's

~" .. • ,.. .. - un ha ppy tr ait a lo t better than th e hydraulic-damped equivalents. The suspension is not faultless . After some use, the fron t forks will bottom when lan ding fro m the t raditio nal downhill jump in the accep ted front wheel fir st to stuff it fo r the turn te chnique. They would do so occasionally unde r other circumstances. There is a so luti on th at is already a standard U-fi x-i t item on Pentons. Cut one inch off the top of a Husqvarna fork spring and stuff it in each tu be to pre load the Italian springs. They wor k better under pressure. Even with th e infrequent distraction of a hars h front end, the suspension did its j ob better than th at on any stoc k motorcycle we've ridden . O n the longer VaIley Cycle Park motocross course , no t a flat track by a ny m eans, it w as im p ossibl e to go fas t eno ugh o r fi nd bumps b ig enough to u se up th e suspen sion 's ca pab ilities . There may be suc h courses, bu t we'll bet m ost of th em ar e caIled Grand Prix circuits .. . or maybe o ne of th e Belgian-Du tch san d tracks af ter four or five mo to s. The n ew sus pension com bined wi th th e new fra me 's po ten ti al all ow the rider to ex plore ne w dimensions in lap times. Rem ember, less is gre at er. The pr ecision in steering, fro nt whe el pla cement, and cornering ability of th is f frame-susp io c.q bo wi) very ~ d iffi cu lt for an y ot he r ma chine to ma tch . You ca n us e the berm as a shar p-angled turning poin t or ign or e it co m pletely to make the turn o r co me off the berm at any po in t yo u wan t and ge t on th e straight line to th e next co m er. The cr itical differen ce with the 360 Penton see ms t o b e th at you ca n do i l with a tre mendous fee ling of co n fide nc e , knowin g th a t all thi s is ~oin~ to work out th e w ay you wan t it 10, so y o u gas it a little harder th e next lap, and the nex t. T he tho ught en ters the thoughtful racer's mi nd, " Is thi s mac hine su ckin g me in ?" But it d oesn 't see m to be ge tti ng yo u to go faste r so it can then surprise yo u and d o bad th ings to yo ur bod y. Ther e 's a fee ling o f person al inde str uc tib ility th at you ge t whil e pu shing th e Pento n 360 har d. Meanwhi le, the sc ene ry is all blu rry , as yo u chance a glim pse o u t of th e co rne r o f y o ur eye. I I doesn 't feel lik e you're goi ng th a t fast but th e top of fif t h gea r, b y alm ost an y moto cr oss sta ndards , provides a low ratio between cran k speed and rear wheel speed. When ever yo u can keep th e rear Metzeler h ooked up. We have ext o Iled th e vir tues of the 4.50 Metzcler kn obby as bei ng the co rrect intermed iary to har d, ro ck y , or dr y tracks if you wan t to race mo t oc ro ss on them. It sti ll is, b ut th e mind and chain-snap p ing bur st of p ow er wh en th e 360 KTM engi ne co mes on th e pip e result s in insta n t wh eelspin if you 'r e a gear t o o low . Mayb e even if yo u 're not. The lead in g edge of the kno bs wen t in two days of ridi ng and it was time to reverse the ti re. What th e Pento n clearly w ants is tr ac ti o n: nice , de ep , Alpine, muddy goo wi th maybe smal l rocks and grass in it. When it has tr ac t ion it is necessary t o ke ep your cro tc h over the tank unless you wan t to ri d e a un icy cle in to th e first turn. Gettin g the maximum advantage from the power package, particularly fo r fast starts, w iIl take prac tice an d ti m ing. Th ere is reall y n o significant low end powe r, but what are you doing lugging yo u r pur ebl o o d m o tocr oss bike an y way ? Mid-range. wh ere th is bi ke like the 250, mu st be r idden to realize the advan tage over other ma r q u e s is a co m ple te ru sh. both to m ind an d mach ine. I t is pipey but not pe ak y . Bu t at t he to p of fifth , trying to p uIl six th gear we ran in t o our fir st no ticeabl e power de ficien cy. T he m otor wouldn 't keep pu Iling or even stay near the powerband. The p lug readi n g with a 18 5 main je t in the Bing was as perfec t as we 've seen . Th e 36m m carb was pr ob abl y not th e culp ri t. Serio us co nsul tati on an d phon e calls to ot her Penton ites and Lor ain , Oh io were foll owed by lit erall y mi nutes of an alytica l though t which led us t o the co n clusio n th at th e air box is th e culprit. Th e still air box on th e new fram e is cert ainly sma ller th an before. Even Carl Cranke su spected it would be more rest ric ti ve, as did we. Had th e Pent on b e en o urs , we would ha ve st uc k in th e high est vol ume filter e lement we co uld find an d drilled holes in th e side pan el to test t his theor y . Horiz on s Un ltd ., a SoCal sho p th at is set ti ng up tw o Pento n 40 0s for the S.C. O .R. E. Baja 5 00, ha s d evised an o th er so lu tio n : rem ove the pl at e under th e sea t th at covers th e top of th e air bo x. A d m itte dly , th e d e-stro ked an d de-b or ed 35 7cc KTM engine (It was o riginally to be in th e 38 0-39 0cc range b ut th ere was no way to ge t it all to the ground in a mechani cally re liable manner .] is n o t a revver but it see m s the hol ey snorkel frame doe sn't pas s enough ni tr ogen-oxygen mi x t o th e vergas ser witho ut some help. If we ge t this pr oblem sor ted out and can hang o n to the machin e long enough to ver ify it, we'll report back . Final emph asis: You are still pr ob ab ly goi ng faster th an you ever have on a motocrosser o r th an you ever may wan t to . To ge t th e res t of the b ad ne ws out of t he way, no te the other Pen to n ism s you'll have to de al with in retu rn for the co nsiderable pleasu r e to be derived fro m ridi ng a new 36 0 . T he left eng ine bracing st rut nu t came off. I t always did o n the 250s, too. It is a weird Teutonic th read , so bu y t he new one and safety wire it and lo ck-rite it. If yo u lose it an d do ' o tice it. ~he n ter 'U The most unique, best-handling rear suspension curre nt ly available on a stock mo torcycle. Chainguide is f irst class. Brake pedal is stronger and now is adj ustable. It f eels much lighter than its 233 readyto-race pou nd s and reponds perfectly to airborne body English . Expert Tom Morris gets the 400 in its midrange, where it likes to be, and squares off on a skatey, dry SoCaI MX course . You had to shift just before wheelspin and wheelstands set in. It took lots of practice to get the right starting drill worked out. Otherwise. the 400 dug a trench, star t to crac k at th e forward engine moun tin g bolt a fte r a while, an d we kn ow yo u don't want to buy new c ases . Th e kicks tarter sh aft has been enlarge d so it wo n ' t crack under kick and kickbac k bu t n ow there isn 't room fo r an a deq uate oil sea l, so it dr o ol s af ter a while an d keeps o n d oin g it. The footpegs sh o ul d pro vide more gri p th an th ey do for the poten ti ally m uddy , we t bo ot so le an d they need t o be sp ring -loaded to sn ap back down . T hey float just a ta d bu t i t is distract ing. D et a il s w o r t h noti ng: Akro nt sh ouldered rims ar e laced to magn esium hubs th at co ntain brak es just bar ely wi thin th e m argin to de al w ith th e ma ch ine's speed, but they didn' t fad e. Th e en gine is sti ll difficult t o work on, th e car b hard to acces s, an d the pipe a bitch to remove. Oh, well . . . The clu tc h see med t o work better than on the 250s we've rid den . It has a Mo to pl at elect ronic ignition with a small roto r mag. A two-lb . boost o n the fly wheel wouldn' t h ur t a th ing plus wou ld m ake yo ur rear tire last lon ge r. It m ay be th e quietest 400 in th e world that can still win motocross. It 's uncann y , even w ith th e little silencer. KTM engines sound like they 're ra ttli ng, detonating, an d o therwise clanking the mselves to de at h. This is seldom actually the c ase. T hey seem to ru n very well . No body re all y knows too much about thi s machin e in ..t he U.S. : yet, includi ng th e Pent ons, There are only.,about 30 in th e co u n try, with a projec ted im po rt number of 2000. So if anybody , especially us, tells you he knows all abou t th e new Penton 400, don't believe him . The res t of these com men ts fa ll under the heading of " T h ings We Didn't Lik e" rather than "Things That Need to be Fixed." We didn' t li ke the ca ble routing as i t ca me fr om the fact ory . Too man y kin ks for our b ourgeoi s style . We didn 't l i ke t h e double u g l y rubber-cove red spring wires that now hold the tank on in place o f the time-honored lea ther bu ckle belt. Bring back the belt ! It wo uld give the Penton 400 th e righ t co mb ina ti on of funk and zip . We didn ' t like the fact that the rear fender came moun ted with both' rubber washers on th e outside so that a vib ration crack started immediately and t he end fell off', We changed the rubber washer position with the new fende r. The rivets that hold the leath er o n the seat we re starting to co m e lo o se after a week. T his co uld annoy somebody who was maki ng payments on their Pen t on . What we d id like was th at the new Pen t on frame and suspension con tai ni ng th e lo ng-awaite d 357 KTM en gine defi ne, in one pa cka ge , all th e good thi ngs that dirt bikes ar e supposed to be. It is the motorcycle th a t wiII make you like ridi ng off -road o r racing motocross or cro ss-conn try best. It is, so far, the be st -handling, th e fas test, the m os t ready-t o-race mach in e in its das.• .· Are you re ad y for that? • 25

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