Cycle News - Archive Issues - 1970's

• • / 11II ~ , • I t t.O r0') ..... Rerou t the ignition wires up the front downtube rather than up the middle of the frame near the exhaust pipe. Use of only the two mounting bolts on the sprocket cover (if used) could prevent an expensive hole in the gearbox case should the chain get thrown. components if yo u maintain a careful eye to detail, and look for the first signs of failure. Bassett Racing Produ cts also offers a special chromemoly rear axle for $ 14.50 which would be a good idea to get along with the aluminum swingarm. The stock axle is easily bent b ecause of its long . length an d the distance between en ds of the swingarm . Once the swingarm problem has been taken ca re of, the drive chain will have no trouble staying on th e sprockets if the chain is adj usted p roperly. Always adjust the chain by sighting d o wn the length of it to see that it feeds o nto the sprockets p ro perly. Never adj us t a ch ain by using the adj u sting m arks on the swingarm. Ch eck the chain gu id e to see th at it is no t ben t, b ut aligned properly to feed t he chain o n to th e rear sp rocket. Since we're on the subject o f chains, be sure to leave the rear bolt off of th e engi ne mo unted sprocket cover if you use the cover. A th rown chain could break the rear mounting bracket and the subsequent stress could break the ca ses. Aluminum bolts in this area also co uld alleviate this potentially expensive problem. In the area of general maintenance here is a check list of details to put a wrench to before riding. Co nstan tl y check front fork tri ple clamp bolts. Check spokes. ? Tape ignition coil to frame in case mounting bolts break. Hackside the sidestand mount off the fra me, file and paint over. :. Use innertube type ' rubbe r band to hold kickstart lever in towards frame. . Reroute the engine m agn eto wires up the front down tube of the frame , rath er than up the middle of the frame near the ex haust p ipe. Wire the throttle cab le so it doesn ' t touch the ex ha ust pipe. r; Sili con e the wires co ming a u t of the 'magneto and the CDI box. Safe ty wire the " bottom rear shock bolts. Ch eck align men t of rear brake b ac king p late so it doesn' t bind when ax le is ·tigh tened . - An d last, b ut perhaps most important on the checklist, see that the rear sprocket bolts are tight. bu t not over tigh tened. Over tigh tening them, or allowing them to get loose can shatter the mounting flange of the rear h ub . If possible. replace the stock sprocket o o o o o o , The airbox has been cut away to allow increased breathing. Use of a double foam. filter, well sealed at the base with grease, is critical hi preventing i1irt from entering the engine. mo un tin g b olts and lock nuts with either titanium or aircraft quality bol ts and lock nuts. The suspension Adding to the RM's excellen t frame geome try is o ne of the best suspension syste~s on any produ cti on bi ke. The rear sh ocks are excellent Kayaba gas/oil un its wi th the gas separated fr om th e oil b y a floating seal. The p roduc t ion sh oc ks are the same as on the works Suzukis, with th e exception that they d on ' t have the external adjustable reserv o irs (filled wi th nitrogen or air) th at help dissipate heat in longe r m o to s, If you aren't an Expert and don't race anything lo nger th an 20 mi nu te m oto s, you 'll h ave no problem wi th th e shocks fad ing o ut. If yo u are an Ex pert rider who races 30 or 45 m in u te m o tos weekly, you 'll want to pick up a better set of sh ocks. , Suzuki offers Roger DeCoster replica shocks with remo te reservoir for $170 a pair, including the spring. U p front, t he S u zu k i / K a y ab a p roduction leading axle fr ont forks with their 9 inches of travel are really good as production units go. They can't p erform as well as t he $3,0 0 0 s pecial Suzuki/Kayaba works forks, but then who wants to spend that muc h m on ey for a set of forks which wear out quickly and you can't get parts fo r. There are things that can be done to improve the stock forks. The first is to . - chan ge to good oil . We recommend 20 weight for the average rider. Brand and weight is personal preference, but the Suzuki team endorses Bel-Ray. The ot her impro vem en t -to the front forks can be made with springs. The original RMs came with fork springs that were too short fo r the long tr avel tubes. Suzuki. who is right on the bal l in offering improvements, now offers an optional fork spring which is the correct len gt h and slightly stiffer. Befo re leaving the subject of front forks, there's one th ing that shou ld always be checked d ur ing th e b ike prepar ation . T here is a slotted steel bushing that fi ts o n the front axl e where th e fr on t axle goes th rough the fro nt fo rks at th e p inch clamp. This slot o n th e steel bushing must line up with the slot o f the fork's pi nc h clamp. If it doesn' t. the steel b ushing won't h ol d the fr on t axle securely enough and th e axle could b ack out. There is no simple cure for the front Chain alignment is crit ical on the RMs. Use Sight adjustment to check chain alignment rath er than swingarm adjustment ma rks. If the slotted steel bushing does not line up with th e slot of the front fork's pinch d amp it could loosen causing the axle to back out. . Special attention is paid to th e routing of cables near handl ebar clamps arid number plates. The kicksta rt lever is bent to prevent hitting the-cylinder and held in place with a rubber band . axle slippage except carefu l alignmen t and constant checking. Basset Racing is working on a kit which will make available a lo nger fron t axle that will accommodate a locking nut. The factory .can cure this problem by simply putting the bolt in from the other side so that ro ta t io n of the front wheel w ill tigh te n rather than loosen the axle. This optional is not available to the backyard mechanic though. The carburetor and throttle assembly Out of the crate the early RMs were not jetted right on the money. Riders 15

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