Cycle News - Archive Issues - 1970's

e ~ I-< Q,) ..0 Q,) u Q,) c Trails End aluminum KTM sideplat es By Phil Stumbo The stock plastic sideplates and inne r rea r fender on the MC5 series KTMs and Pento ns are notor ious fo r cracking. The KTMs of our acquaintance had a n 'a verage life spa n of six to eigh t races. Ours lasted tWO months, ra cing every other weekend in the desert . - Trails End , a San Leandro. Calif. , shop sp ecializing in th e A ustrian marqu e , has pol ished alumi num sideplares and an inner fende r retailing at similar to original equipment prices. Mounting the aluminum products ranged in difficulty from easy to . terrible. Due to the difference in th e mounting holes from bike to bike, th ey do not come pre-drilled. The righ t sideplate was drilled , rubber-mounted and went on easily. The left sideplate probably would have gone on as easily, bu t th e KTM 400 we mounted it on had a large -capa ci ty Vesco d ese rt tank. The front corner of the pa nel was blocked by the ta nk, so we be nt the leading edge down undern ea th the fr ame tube, After nearly a yea r of steady racing, running in t he top five overa ll at CRe/DRA d esert races, the sidepla tes are still usable. There is on e cr ack in t he me tal where we bent it, bu t nothing serious. The inner fend e r had to be hammered ou t to reach t he frame tubes for mounting. It cracked durin g use , but was going along fin e un til th e silencer came off during a race and was pushed down there by th e tire. I had to throw it awa y. Still , in comparison to th e longevity of th e stock parts, all three are highly recommended . Trails End 16394 E. 14th St . San L eandro, CA 94578 (415) 278 -1565 Dirt Werkes R&D Suzuki stand By Da le Brown 14.. D irt W erkes R&D , a no rt he rn Cal ifornia manufactu ring firm , has a line of bik e sta nds for m ost popula r MX ers, distrib uted by Hi-Poin t. ,We asked for. a stand for a Suzuki RM250 C since we were testing th e bik e at the time. The stand we got was de signed for the " B" model but worked fine , except for missing skin around the knuckles caused when th e hand hir 'the larger "C'{rnodel silencer. That was our only complaint. It 's ea sy to use, th e three-point support holds th e bike rigid ly (handy when a nut about to be removed has th ree applications of Loctite) an d th e sta nd is well made . It get s o ur recommendation . See your H i-Point dealer. then hope it will still be there when the other side is adjusted . Having a nother person around helps. But the $29 .95 stand is adjustable and we used it while we work ed on Suzukis, Yamahas and CZS. It is more compact than the Dirt W erkes unit , an im po rt a nt po int if your va n / truck/ t r a ile r is already crowded. We recommend it on th e proviso that you be patient while propping up the bike. See your Full Bore d ealer , or Full Bor e West 13712 Alma Ave. Gard en Grove, CA 90249 them down to the friendly folks at DC Performance Specialties for laci pg. Then the front wheel assembly was mounted on the official Cycle Ne ws test bed - a RMI 25 B Suzuki. The bike was run at several SoCa l motocross courses and out in the desert. Running with a pair of longer shocks on the back to keep the frame geometry more or less status quo, we discovered the 23 -incher really does roll over bumps better, especially braking ripples that build up before corners. However, sand is the 23 incher's prime element. It ad d s stability and gives confidence to the rider by' eliminating t he a rm -wrestling required when the bike isn't goi ng fast enough to plane on top. The only drawback we fou nd was noted by one of the faster pros around , who felt the set -up didn't turn fast enough on th e prevalent SoCal adobe. We would really like to see a bike designed around th e 23-incher so that the advantages of the tire and rim can be maximized without side effects like changing the frame geometry. While the Yokohama/D.l. D. duo might not be the hot set-up for adobe and slick motocross courses. it is recommended for sand and desert use. Just make su re you ha ve an inch and a half clearance with the forks bottomed out. Or you might be over the bars and bummed ou t. R&R water-cooled head By Dale Brown Bolger/Full Bore bike stand By Dale Brown In contrast to th e Dirt Werkes stand, Full Bore decided to market a Joe Bolger designed model th at would fit just about any bike . T he vertica l member attached to th e handle fold s and pivots , th en sta ys in pl ac e when weight is applied . The biggest problem wit h the Bolger Full Bore stand is that th e folding a rm ma kes it d ifficult to line up the bott om frame tubes with the sta nd. O ne mu st peer over the side of the bike to see that one side is in pla ce, Yokohama/D.I.D. 23" tire/rim By Da le Brown A few yea rs ago , when most Japanese tr ailbi kes still had IS -or 19·inch front tires, th e cry went up for 21 -inchers. A larger tire, folks rea soned , would roll over bumps easier and resist getting . snagged in ruts . The 21-inch front tire became an industry sta nd a rd for offroad mot or cycles. Now Yokoh am a has a 23-inch front tire , a nd D.l.D . has a rim to match . T hey've been availa ble for a bout a year, and 125cc National mot ocross cha m p Broc C lover used the m in the Florida Winter-AMA series . We assembled all the ite ms a nd too k _ The Cycle N ews test Suzuki RMI 25 B got a new head - the R&R Machin and Products water-cooled head. W tested th e version with the radiator; there is also a water cooled head that uses a single hose loop to dissipat heat. The head works on a thermosyphon principle - heat generated by the head causes the water to rise to th radiator and cooler water takes its place'. By a p u re eval ua ti on the head unquestionabl works . There is no pow er fad e , whether you run a 3D- m inu te rnoto 0 a GO-mile desert race. There is mor power to begin with because th e head is m illed sligh tly ( A ce less cha mbe volume) for more cranking pressur e. Since th e hea d runs so much cooler , th e jetting can be leaned out all th way through the ra nge . The leaner th

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