Cycle News - Archive Issues - 1970's

~---::""-':'::"'..,.r---,=,,:"'r":~"'IC='------""-----" M " '" '" Q. M .... Cl o N YAMAHA'S SC 500 lJ) ~ w Z W ...J U >- U YAMAHA YARDSTICKS BIK E Typ e Bo re/stro ke . . , Disp lacem e nt . , Lubric a tion ' T ran sm ission Cl ut ch Carburetor Wh e elb ase Han d le ba r widt h Fork travel Tire s Fuel Capa city Oil tan k Wei ght (w e t) - two -st ro ke, re ed valve, 7 port , si ng le , . , , . 95 m m / 70m m ,, : 495 .9 c c Au to lu be a nd p re-mix -l-specd , \~ e t , m u ltiple d isc , V M:\RSC , ~( i kun i , 5 5 .9 in c hes , , :\ 7.4 in ches 7.52 in ch es :~ . 0 0 x 2 1 & 4 .60 x 18 2 .4 ga llons 0. 6'1 quarts , A b ou t 265 pounds DOLLARS Piston ~ $ 16 .8 0 CI;'tcb lev er $2 .90 Shift lev er $ 3 .96 Front fender S 12.0 0 Rear fender . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 9 .60 Su gge st ed retai l About $ 1225 main jet an d two notches up o n the needle was a good start. The slide is a bit ch to Ret back in th a t 3 8 m m Mik un i b e cau se th e ne edle likes to m iss its seal. T he NG K B8EV is replaced w it h somethi ng a wh ole lo t cooler, an d th e re sult ant co m b in a tion red uce s p in gin g to a b a re min imum . T he e ngi ne eve n pulls a bi t st ronger and is a whole b unc h h appie r. A fe w more - d itch e s ar e s du g with the 500, shutti ng off freq ue n tly to c o o l it d own , and w e 're n ff to the m o to cro ss co urse. Eve ryone w as just a little afrai d to ven ture o n to the m o tocr oss c o urse , so in lie u . of m y f irst "winnin g" co in to ss I g o t the initiat ion this time too . Re luc tant troope r th a t I am, I ve ntured o u t a mong th e mini b ik es. l 'ms till ver y a fra id o f th e eng ine an d j us t p lon kin g aro und. T he engin e p ulls o u t strong ly from lo w R PM in corn ers, an d a s lo n g as y o u tre at th e th ro ttl e wit h re sp ect n o t hin g fri gh tenin g h ap pens , A m az ingly en o ugh wh en I t ry to do berm numbers at low RPM the 4.60 re a r tire like s to d ig in an d try to p ut me out in to a fiel d . Guess I' ll h ave to use a few more R PM . T ha t w orks a w ho le bunc h better, and th e dirt flie s. The SC -500 carries a C Ol flywhe el m agn e to . I t wi ll spar k all th e w ay down t o slu gging speed. The :l8 m m !\Iikuni mi ght be c o nside re d a b i t bi g eve n for the 5 0 0 . Wit h a smaller ca rb - say :\4 o r 3 6 - it w ould probabl y pu ll ou t like it s fo u r -st ro ke brethren . The tran sition s tage o n the. c arb ure to r st ill see m s a bit lean and a c horus o f pings will o cc asio na lly w aft thr ough the air. . For a h eavy mo t o rcy cl e th e Yama ha turns pretty well . The handling isn' t wh at y ou w ou ld call light and it re sp onds slo wl y to com man ds . All th e litt le movements in corpo rated in riding a sm aller and ligh ter bike - a round fade into sl ow turning mo tions. The s us pe ns io n is plush . The front forks se em to re m ove o bjec ts from th e p ath o f t he SC -500 rather than a b so rb in g tb em . I am more relaxed than I have eve r been on a mot o cross course be fore. A mazm g, m y arms are rel axed, m y head is drooping, m y toe is lolling under t he shi f t lever wa itin g for a ch a nce to shift ( it sel dom com es). Sure h ope ( don 't fa ll aslee p. Down th e straight an d over the jump the re is a little bit of exci tement. Wo w , I ge t t o use third gear. Wo w , speed builds ve ry rapidly and th e jo urney th ro ugh th e air seems to take forever. Landing is smo o th . 11:0 j olt , just kin d of a squish , an d I think about gassing it , but don't. T he rea r brake is loosening up no w an d works great. Th e b u mps are hardl y fel t thro ugh the rear wh eel. I gu ess the reser vo ir sh oc ks m u st b e w or ki ng: p re tty w e ll, too. In these m o re pushed circum st ances, the fron t co n tinue s to work b ut is only j ust a m atch fo r th e m a ss of the Yamaha, no m ore. Now into this corne r, we'll go th e ins ide route. Applying about six h airs of thro ttle the re ar end steps o u t and JUS t stays th ere. A rut a ppears an d th e re ar whee l di sappears it , n o sweat. T he re ar en d fall s b a ck int o lin e with o ut a sna p , j ust sort of se ttles b ack , Wb en ( ro ll on the thro ttle th e 5 00 surges fo rwa rd , wben I sna p i t o n the rear wh ee l sp ins . A le sson is le arn ed. A ft e r a whil e I b egin t o run ou t o f gas. T h e tan k h ol d s 2. 4 ga llo ns and mileage is n eithe r grea t no r abo minable. Still , yo u w on 't ge t to o tired b efore th e 5 00 sp utters t o a h alt , Pu lling in to t he pits,Tm n ot at all ti red. Surprisin gly eno u gh, th e SC -500 d oe sn ' t requir e p ush in g aroun d (e xce p t wh en ou t o f gas ), an d it's pre tty ea sy t o ri de . A ll o f the fo rce s an d strains o f mo to c ross must b e going some whe re tho ugh, S i tti ng o n the b ack o f the van the stress an d st rain sta r ts to sho w up , The bleedin g steeri ng he ad h as shaken lo o se and m o st o f tb e be ari n gs h ave gotten awa y . A n d m y L ord , look a t th e rear tire . T h e middle kn obs are very rounded alre ady . O n e mo re day a n d t he tire w o u ld b e w orn out . The Y am aha 500 is goi ng to eat tir es much fas te r than the rub be r p lant in y o ur back p o cke t .can gro w the m . A fe w crac ks are a ppearing here and th e re. to o . T he SC ·500 is going to requ ire m or e m ain ten an ce if us ed for m oto cro ss tha n y o ur ave rage Ya ma ha . Then again , it wi Jl s till re qu ire less than most Europea n m o un ts. T he 500 w asn' t slow aroun d a m oto cros s c o urse , in fa ct an Expert co uld m o ve it arou nd ;n a p retty b ig h ur ry . Still , th e 3 6 0 will re main th e ho t setup fo r 5 0 0 class moto cro ss in th e Yamaha lin e. The SC -500 was j us t a bit t o o slo w handling. Y ou migh t c all it the Lin coln Contin ental o f m otocros s. Ah -hah ! Yamaha cal le d it a " Scram b ler " , th ough. Well h eck . it's n ot a b ad mot o ero sser, but just im agine ge tti ng a ni re , big trials tire fo r the re ar and go ing o u t to th e TL Wbat a d ynamite 5 0 0 'IT bike, o r for that matter a roug h sc ram b les bike . N o 5 0 0 class bi ke cou ld touch it p ower-wi se, an d it slides re asonabl y . J10t d iggit y l Or yo u cou ld take it o u t to th e des ert. All yo u gu y s wh o d i& bi g de sert sleds , h er e's on e that handle s re ason ab ly and goe s as fa st as y our wildest dreams. Y ou 'll have to ge t a bigge r gas tank and o il tank , to o, if you want to stick with oil injection . A dd some di fferen t b ar s and you' re ready t o go. Or yo u guys wh o a lw ays w anted a 5 0 1 Mai c o to pl ay aro und on. T he SC ·5 0 0 is sim ilar in e ffect , and won 't require the intense ma int e nan ce . It' s a bl ast to play o n in a big ope n field . Wheelies, slides, a ll k inds an d va ricties of sh ow-off h ot dogg ng . It i will give yo u the p le asure o f h a vin g a bike wh ich is five cc fro m bei n g the w orld's b iggest two -stro ke .single. You ca n r u n o ve r lillie kid s on min ibi ke s, to o . If n one o f the se th ings appe a l to yo u, y o u can buy one a nyway . an d h ire o u t to loc a l farms as fie ld p lowe r. Jus t w in d h e r u p an d d ig.

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