Cycle News - Archive Issues - 1970's

Cycle News 1970 08 18

Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles

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TEXT AND PHOTOS BY ED YOUNGBtOOO Harley-Davidson's new super racer has failed to come up to early expectations for two reasons. Flaws in design do exist, but much of the disappointment is because people have expected more of the XR than they should of any new bike right out of the box, racer or otherwise. But a realistic look into the motor makes one encouraging point. It isn't going to take a decade to sort out the problems. for all of that was done with the KR, and much of it will apply here. Text and Photos by Ed Youngblood Of the new XR, Harley-Davidson's product1oo racer, apiece of factory literature states, ..All you do is add gas, oil and one rider, anxious for winning." However, the results of the XR's short history on the track would suggest that the winning combination is not so simple. Riders of the new machine - incluc!1ng the fac10ry team riders - have suffered one breakdown after another, and even wilen the machine is running reliably, it appears that gas and oil alone aren't enough to make it competitive. For example, witness Mert Laww1ll, the number one National rider and top Harley man, switching back to the old KR flathead in his recent Ascot Park victorles, after several dismal outings on the XR. We wondered about the new racing b1ke's fa.llure to come UP to expectations, so we found one that we could "get into," seeldng possfble causes for the less than w1DD1Dg ways of the XR. The photographs aDd statfstlcs in this arUcle are from a machine that was purchased in MUwaukee, brought to Oh1o,aDdprompt1)' torn down. Its cylinders have not contained fire, except for a few minutes on a dynamometer. It ts owned by an 01110 rider with a decade of experience on KRs, Sportsters, aDd Sprints, aDd it is being mod1f1ed by one of the very good Harley-Davidson tuners in the East. It is being treated with care because its owner knows that more than mere gas aDd oU must be added to any racing machine. He knows that there 1s really no such th1ng as a stock production racer at least not a truly competitive one. Yamaha (with the RR2) and Norton (with the Manx) probably have come as close to BEACH C'ITIES CYCLES SOUTHERN ORANGE COUNTY 1101'0· f CROSS HEADQUARTERS HUlqvarna - Yamaha - Greeves Honda such a beast as anyooe can, but noth1ng w1ll win r1ght out of the crate. (tit does, you're not rtd1ngin verY fast competit1oo. ADd that br1Dgs us to an 1mPortantpotnt we would Uie to make before IaIlllch1Dg into technicalities. Harley-Dav1dson is not to be 1od1cted for all of the XR's problems. The XR's performance has been said ma1nly because too many hapless Amateurs (and a few Experts who should have known better) thought they actually could purchase a sQPer racer in a box. As we said, there's no such th1ng, and that is true of any manufacturer's machIne, advert1s1ng literature notwith-' standing. But unfortunately for HarleyDavidson and themselves, too many people have jumped into the 1970 season th1nIdng they bad found an easy way to the checkered flag. Theoretically the XR' s perforrnancecan be considerably boosted by a whole- saie shedding of excess weJgbt, and believe us, there is plenty to be shed. BasicallY, th1s d1et1ng is what is being done to the mach1ne we studied. Few goodies are being tnstal1ed, for the owner and tuner want to take ODe step at a time, first conv1ncing themselves that the mach1ne will run reliably and powerfully wilen properly prepared. Two results are hoped to be ach1eVed by trimming pounds from the XR. First, a lighter bike is easier to muscle around the track. But more imPGrtantly, an engine with less reciprocating welgbt w1ll rev UP quicker, reach its power range sooner from an 1dle, aDd consequently be more manageable in the rider's hands. It is in the XRs rec1procating parts that Harley-Davidson has let very 00racer-like iron slip by. Some weight reductions are questionable (they may FE PLUS...lF YOU CARE ABOUT YOUR BIKE. FE PLUS FUEL ADDITIVE: .1ne...us Plul life ·D.llvers hi"', RPM', and more pow., ·Ine,.ases mllole ·Makes st.rtlnl easl., ACCESSORIES -SPECIAUSTS 525 N. EI CamillO Real Calif. 92&12 (14) 452-&141 san Clemente, CVamaha of~l onte MDtOCl'lss and Desert Head....,_s fw tile sa. Gallriel Valley MOST COMPLETE YAMAHA PARTS SUPPLY IN STOCK IN THE VALLEY RICKMAN BARS· GIRLING SHOCKS • CERIANI SHOCKS • HALLMAN GLOVES· NITO TIRES TRELLEBORG TIRES • BARUM TIRES YAlAHA OF EL MONTE Slies . . 5erYice 2159 No. Durfee Awe., EI Monte, Calif. U132 (n3) 442-5800 FE PLUS OILS: ·Reduees pll/lloullnl . ·Ellmln.te ellbon build up ·Cuts eJdlaust IUlllls ~ Iaere.ses powe' -Reduces IIIlln. well ii!!~~;~i Mr. Dealer: FE PLUS prDduets DO. available lIIrougil Yamaha IntnatiDlal, Pacer C,nsalillated Industries, FrH Deely, Gamey & HDlt. Far furtIIer prDlIlIet i.......tion write: SCD/MAR ENTERPRISES INC., 15120 Vell1m Blvd., EnCiID, Calif. !131&

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