Cycle News - Archive Issues - 1970's

". ". ~ 0- M .... S!? I!l ' " ::> .., CO en ~ w Z W ..J C,) >C,) '" .' A d ifferent beastv than the ones of yore - the 360 MX works. . *********** •••••••••• *•••• ****.**.************ • * * ~®@ £ YAMAHA EMECHS SPECS T ype Displ ace men t Bore a nd Stro ke Compression Rati o Lubricat ion Sy st em Start ing Syst em Tr ansm ission Trans. Gear Ratios 1st 2nd 3rd 4th 5 th . . " Carburetor ·A ir Filter Wheelb ase Min . ground clear ance Front Fork Travel ~ Caster Trail Ign ition Syst em Fuel Tank Cap acity O il Tan k Capac ity 2 stroke, single 7 ·port, t o rq ue induction : 351 cc SOmm x 70 m m 7.43 :1 Auto lub e prim ar y kick start 5-sp eed constan t mesh , .' , ' : 36 11 6 2.250 33 /20 1.650 29/23 1.261 26 /2 6 1.000 , 231290.793 VM34SC , Mikuni wet , fo am ru b be r , 55.9" 8.S " 6 .8 in. 59 deg ree " 5 .5 in . C.D . I. ~ 2.4 gal 0.69 qt Oil tank is small and down low . by Dave Sch o onmak e r Photos b y Ran dy Dietzel , Tom Cu lp, an d Schoo n make r I f w e wer e giving away a "mo st improved motorcycle o f th is hal f cen tu ry ' awa rd , we mi gh t give it to the Yamah a 360 MX . It wouldn't be diffi cu l t t o a c cuse Ya mah a of s uc c umb ing to an o vert learning ex pe rience . A m o to crossI cc m pc ti ti on r ] ver sion o f Yamaha's 360 en d uro has bee n with us n ow for fou r ye ars. That first vers ion w as an ama zin g motorcycl e . It was fa st, p ip ey, noisey and had all th e gre at handling attributes of its en duro relati ves. In short , the 197 0 360 Yamah a wa s an interesting b ike , bu t a racer o nly for the hardy . In 19 72 Yamah a ch an ged the ir ori en tatio n an d began buil din g .hjkes gen uin ely for th e p urpose of m o t ocross, inst ead o f adding an exp an sio n cham be r and some wild p orts to on e of th eir e n d ur o s • It was an i n c red ibl e improvement. The '72 36 0 />I X began to beco me a viable co m pe ti tio n ma ch ine . It still wa sn 't in th e league wi th Eu ro pean moun ts, th ou gh. It was pipey , and tho ugh the fo r ks were a vas t improvement and the frame was a ne w design, h andlin g was st ill a little on the th rilling side. A lo t of th e 197 2 3 6 0 MX h andlin g jo ll ies came fro m th e so me w h a t s u d den powe r band, c o m b i n ed wi th the n ot-so -sudden shocks . T he 197 3 Ya ma ha RT -3 ' MX has gon e a long way s to wa rds getting o ver the gremlins of y o re. Man y of th ose gre mlins evaporated wi th a re-desi gn of th e engine. For ' 73 the 36 0 is a close relative of t he n ew 5 00. It is basically a debored mo del of the SC 5 0 0. It gets the o mni -p has e b alan ce, ree d valves, a tricky co mpression rele ase capaci tive dis charge ign it ion, b ut in departure , keeps a five -speed ge ar box. T he mo tor Air filter sheds dirt - works great . works in a mu ch more useful mann er than in previous years. The real beans in the 36 0's motor are still fo-und up to p on the rev range, but new for 1973, it works down low, to o . Probably due to the additional weight of the ornni-phase balan cer and the strong spark of th e COl , the 360 responds cleanly from su rp risin gly low RPMs. It responds at su ch low RPMs th at it will probably never bother y o u in a mo to cross or desert even t. In fac t, the bike was run by o ur s ta ff in an en d uro and was found ca p ab le of slugging away in a muddy, sn owy en d uro without co mp lai n t. On e sh o uld n ot ge t th e impres sion that the 36 0 sh ines on low end torque, but it will tolerate that sort o f treatmen t , T h ro t tle res pon se is clean, as stated before, but th e re act ion is more subtle t h a n prev ious m od els . No thi ng unexpected h appens wh en mo vin g o u t o f slo w c o mers at near ful l tilt. T he p ow erband is eve n so mew hat co n ven ient, as the power build s as th e revs rise during exit from the co rne r, A s for sheer .p ower, th e 3 6 0 gives away 4 0c c to m an y of i ts rivals , yet will keep up with mo st in a s tra igh t lin e race. In numeri cal quantities of h orsep ower it is right with its competitio n . T he o nly thing it will not d o is accelerate from low RPM s with so me o f its rivals. It will require a slight al teratio n of riding style for some . A subject of frustrati on on many Japanese mo tocrossers of the past has been detailing. A tricked o u t en d uro bike will gene rally leave so me thing to be desired. Japan h as caught on and th e motocross bikes co mi ng o u t o f J apan for 1973 will make a fe w Euro pe an manufacture rs stre tch to match th em in d et ai lin g . The 3 60 Yam ah a has surprisin gly few ta ck- ons fro m othe r m odels in th e Yamaha lin e. The grip s and the levers a re th e on ly o bvious carry ove rs an d also th e b igges t gripes. T h e levers break t o o easily (Bu t th ey are cheap .), and th e grips are t o o h ard and a tad slip pery . T he h andlebar s bend to o easily also, but Yam aha made an des ign . a tte m pt a t a goo d Unfo rt unate ly , they kin d of over-did th e big d irt b ike bar idea; th e b ar s are actually a bi t to o wide for most peo ple. T he 36 0 is deli vered wi th o il inje ction , ye t require s premi x too. A bit of hassle , b ut it migh t be wo rth the while in lo n gevit y . T h e oil tan k h olds abou t seve n -te n ths of a quart which will s las t about two tanks of ga. . At ab o u t 50 mi les to a ta n k o f gas , y o u can ex pe ct t o ge t th rou gh a dese rt ra ce o r Gran Prix on th e 7110 of a quart. The filling me th od is qui t e clever. In o rder to keep th e weight lo w, Ya maha has put th e o il tan k lo w on th e bike . and on th e left si d e. Th is makes th e tan k very inacce ssib le, so a filler h ose h as been strung t hro ugh to the right sid e , and a clip hol ds i t up ben eath th e air fil ter co ve r. All th in gs co nside red (the t an k po sition an d size) it's n o t to o bad an arrange me n t. T he seat is a co m fo rtable ite m fo r any use we co uld th ink up. Paddin g is su fficien t and the shape and tex ture make m o vem ent eas y . T he foot pegs are Yamaha metal j o b s which ar e quit e acce ptab le. The fen de rs ar e durable (p racti cally unbreakable ) plas tic, as ar e th e side co vers . the number pla tes. an d othe r app ropriate piece s. The o ther nice n on -metal item o n the bike is th e throttle assembly . wh ich has be en im p ro ved even ove r former models. One of th e p ossible very st rong po in ts on a Yamah a mo tocrosser can be b rakin g; Can be , because , despi te th e fact that rear hub floats well : th e rear gra b ber is so me times to o gra b by. Our test sle d was a classic examp le of th at problem wh en we fir st got it. The rear brake was de cidedly too gra b by, Afte r a few rac es it lo osen e d up, but the re ar brake always required su b t le inputs. Th e fro n t b ra ke was p len ty powerful an d h ad good feel. It was possible to use it to its utmo st in an y sit uatio n , e xc e pt on

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