Cycle News - Archive Issues - 1990's

WORKBENCH By Brian Catterson @ Roadrace prep, part 1:safetywire n r oa d r a cin g , sa fe ty wi re is a necessa ry evil. No m atter wh ose rule book you read, th ere's no esca p ing ·th e req uireme nt th at you secu rely fasten a variety o f you r m ororc y c l es components. Even if yo u' re not a road race r, sa fety wire (or lock wi re, as it's so me times ca lled) is a good idea since it prevents vario us parts a n d/ or flu id s from pa n in g co m pa ny wi th you r b ike. . Though speci fic rules vary from club to cl ub, all road raci ng o rga nizatio ns require that yo u wir e a ny potent ial so u rces o f oi l o r fluid . leak s. These include (bu t a re not limited to ) the o il drain plug, o il fill er ca p, oi l filt er o r its retaining co ver, oil level sig h ting window, fork fluid drain bo lts, coo la nt drain bo lt (s ), radia tor ca p , a n d a ny lines leading to a radiator, o il coo ler or , in the case of a dr y-sump motor, a n oil tank (wh ich is sometimes loca ted in the frame ba ckbone). These ru les exist in th e hope that you r bike won 't leak oil or othe r fluids o nto th e racing su rface, which co u ld ca use so m eo ne (maybe even you) to crash . At th e very least , i t will pr event yo u from e x pe r ie nci ng m ech ani cal probl em s ca used by not ha vin g a ny o il o r wa ter in yo ur engine. In addi tio n to wiring th ose parts wh ich co u ld potentially leak o il or flu ids, many cl u bs a lso req u ire that you wire th ose pans wh ich co u ld result in a ca tastrophe if they came adri ft. T hese include the bo lts holding your brake calipers o nto I your fork legs and swi ngarm , the brake to rque arm , you r a xles a nd axle pi nc h bo lt o r cap, ch ai n adj us ters, chai n master lin k, ex haust header bo lts, and the n u t! bolt holding your ex haust system at its rea rmost mount in g poin t. And whi le few clubs req u ir e it, ha nd grips shou ld be wired , as shou ld foo tpeg rubber s (so me sa nc tio n ing bod ies, suc h as th e AMA , require rubber -co vered foo tpe gs ) a n d sh ift or brak e lever rubbers. Now , o n to th e how-to : To safety wi re a nut or bolt, begin by determ ining how you want to ro ute th e wire. T he sim p lest wa y is to wir e two o r more bolts together (see figure A): thi s works ex tremel y well in th e case of brake ca lipe r mounting bolts. Since you want th e wir e to p ull th e fastener in th e tightening directi on , kn ow in advance wh ether yo u ' re dea ling with right- or left-ha nd threads. Begin by assu rin g tha t th e nut/bolt in question is p roperly secured; usea torq ue wre nc h if a torque value is g iven in your sho p manual. Next , determine wh ere yo u' ll need to drill th e hol es in th e fas tener, a nd mark th o se locations with a magi c marker. . T he drill size yo u 'll need depends o n th e wire gauge you 're usin g , but 5/64in ch , #50 or #52 dri ll bits ar e a bo ut rig ht. You wa nt to drill as straigh t a h ol e as possib le through th e fasten er (see fig ur e B), bu t it needn 't be perfectly stra igh t. In fact, ra ther th a n hol d in g your electric drill a t a shallow a ng le a nd a tte mpting to dri ll straigh t through , try centerpunchi ng the flats o n both sides of th e kn own to ca use flat tires (a nd they rea lly hun if you kn eel on theml) Once th e wi re is twis ted, feed one of th e loose ends th rough th e hol e in th e seco nd fastener (or arou nd th e fra me spar or what have you ), twist the two en ds together , a n d cu t it so that you have a bo u t a quaner -inch -Ion g pigtail. Bend it down so th at it 's flu sh . There are some cases wh ere safety wire is n ot th e o n ly mean s of properl y secu ring a co m po ne nt. For exa m ple, in th e case of coo la nt hoses a nd o il/fuel lines, most cl ubs simply d ictate th at hose clamps be used. How ever , i t is still wonh the effon to safety wi re the hose clamps by wrapping a pi ece of wire around the hose, twisting it as it runs through the slo t in th e h ose cla m p 's screw , and wrapping it aro u nd th e hose o n th e o the r side of th e clamp. Hose clamps ca n a lso be used to secure . sp in-o n type oil filters. Sim p ly tighten the hose clamp around the filter , then run the wi re aro und part o f th e hose cla m p, through the hose cla m p 's screw slo t, and a ttac h it to a neighbo rin g frame spa r. In so me in stances, suc h as o n a x les, sp ring o r R-cl ips work well , but th e en ds shou ld be wi red closed. T he excep tio n is in en d urance raci ng, where a n un wired R-clip pe rm its quicker whee l cha nges. Also, when dealing wi th for k drains, wrapping th e lower fork legs wit h duct tape is usally acceptable. Nex t week , we' ll look a t some of th e o the r req u ire m e n ts of road race preparation. 01 p roposed hole. a nd drilling from both sides a t a steeper a ngle, meeting in th e m iddl e. You'll need to ben d th e wir e a iitt le in o rde r to feed it through the hol e. Don 't drill a t too steep a n angl e, h ow ever , or you wo n ' t be ge t th e wire through a t a ll! T here are a number o f gizmos o n th e market that su p posed ly "si m p lify" drilling fasten ers for sa fety wir e - so me work, so me don't. Consult a fell ow racer or a trustworthy dea ler to find o u t which is whi ch . In li eu . o f drilling your fasteners, wash ers wi th tabs to accept sa fety wire ma y be used . These a re readil y avai labl e from m ost motorcycle accessory deal er s. Once you've drilled th e hole(s), rei nsta ll the nut/bolt(s). Cu t off a n excessi ve len gth o f safety wire, feed it through th e hol e, and double it up. Determine how long a run it is to th e .poi n t a t which th e wir e is to be a ttached - wh ether it 's , to a nother fasten er, a frame spar, whatever - th en grab th e wire a t th at point wi th you r trusty safety wire pliers a nd twist. You want a tight bra id , b u t not so tigh t th at th e wi re br eak s. Experiment to fin d out how tig h t is too tig ht . If you do break th e wire, be sure to dispose of it in a proper trash receptacle. Sharp bits of broken wire have been e 1990RM 125 1990 YZ250 1990 SUZUKI RM 125 PIPE SHOOT-OUT 1990 YAMAHA YZ250 PIPE SHOOT·OUT 55.0 50.0 3 5 .0 45.0 :. . 3 0.0 FMFGOLD 40.0 : : : : :~ •PRO CIR CUIT 35.0 2 5.0 : : : : ::: . : : ::: :: : : :: : :: ::::: :: : : :: . STOCK 30.0 2 0.0 15.0 25.0 .... ... ... ... ... .. ... ... ...... .... ....... ... ... __ . •_ 10.0 20.0 • • • •• • • • • • • • • • • • • • • •• • • _ O- __ _ ~_ +-~ . 5.00 t-::.::-==--=-.:_ -...:.::=::...:--: :.::.:: :.: :...:.::.::::::..::::..:.::~:..: :...:: : : : :~ , ~ ~-_ , 4000 5000 6000 7000 8000 9000 10000 fnglneRpm PSI 52.3 HP SrOCK 47.6 HP FMF 48.4 HP PRO CIRCUlr 48.2 HP 5000 " "" , . ,_ . _ - "" ,-. " .- """ ., - 6000 7000 , 8000 ,, ._ - 9000 ~ ~- ---- _~ - 10000 -, ,, , . , ,. , - - -- - _ 11000 12000 fng lneRpm PSI 36.8 HP SrOCK 34.5 HP FMF 33.7 HP PRO CIRCUlr 34.6 HP Yankily yankity yank. You've heardit all before, Some pipestugat the truth about howmuchthey actually increase horsepower. But onlyone piperemains the champion of performance by comparison. PSI. ; In yet anotherdynoshootout, wesaddled up a box stock'90 YZ 250 and a '90 RM 125 withthe three leading pipesyou can buy off the dealer shelf, to findout whohas harnessed the horses-cor who's pulling yourleg. I's Andthe testconcludes. On the yz 250, PS pipepulls an incredible 4.7 Horsepower over stock, whilePSI's RM 125 pipeproduced a healthy 2.2 additional Horsepower overthe competition. FMF and PRO CIRCUIT once again ChU2 and tug way helow. PSI Pipesproducemore tractable, useable horsepower than any other brandon the ? PSI, INC. 0 RT 2, BOX30'l 0 WILD R OSE, W 54984 0 1 41787.2430 0 FAX (4141787-3764 I 41 market Guaranteed. So, what's iI going to he. Horsesor legs 17

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