Cycle News - Archive Issues - 1980's

So I loaded up the XR and headed up through Cajon Pass for some suspension and some external breathing modifications. The first thing we decided to do was cure the problems in the front forks. Ron agreed that the compression damping was much too hfgh in the forks. After extensive testing, Ron finalized the following modifications to the forks: The damper had two extra compression damping (0.21 9-inch) holes drilled in them, the first 4.0 inches from the bottoming cone, the second 4.5 inches from the bottoming cone. All holes were deburred and chamfered. The stock seals were replaced with special seals that Gator Products sells. They feel the stock sealS have too much stiction. The stock swiper seal was also discarded and replaced with a Gator Products Swiper. Ron likes to run without the fork boots but Ilike them for their protection against dings. For riders under 220 Ibs, Ron recommends the Gator Products light fork springs with lOw Spectro fork oil measured 4.75 inches from the top of the forks (no springs, forks fully compressed). For riders over 220 lbs; the recommendation is to use the stock springs with lOw Spectro at 5.2 inches as measured above. When pouring the fork oil in, it is very important to stroke the forks a few times slowly to get all the air out for an accurate measurement. The rear shock was exchanged for a modified Gator Products shock. Ron modifies the stock shock to provi~e different damping, Three Stage Valving he calls it. Ron also replaces the shock seal with a special shock seal that he markets. The seal is available separately. The stock spring was replaced with a XR350 spring. You would think the XR350 spring would be lighter but it actually carries a heavier rate, since the XR350 has a higher leverage ratio than the XR500. For big boys like me, Ron would like to find a little heavier spring. Progressive Suspension just came out witll one for the XR500 that should fit the bill. The recommended 'preload on the rear shock is 253mm for riders up to 225 lbs. and 251mm for riders over 225 Ibs. The bike should sag about 100mm with the rider on the bike. With the suspension taken care of we turned our attention to the motor. We wanted more power but without tearing into the engine. Gator Products has two stages available. The first consists of a Gator Products pipe that was developed with International Motorsports' airbox modification for better breathing, a new air filter and carburetor rejetting. The Gator Products pipe is a megaphone for racing only. While silencing is built in, the pipe makes the' bike too loud for any riding around civilization. It does sound good though. It's not obnoxiously loud but the db level is certainly up there. The Gator Products pipe is swedged where it slides onto the stock headpipes, allowing the stock clamp and gasket to be used. First was good but we had to file the rear mounting bolt hole slightly for bolt clearance. Ron feels the stock airbox is the biggest hinderance in making the big thumper breathe. He cuts most of the top of the airbox away and then installs six Uni-Filter Air Vents in the side of the air box lor maximum breathing. He replaced the stock air filter with a Uni-Filter Pro-Camp II dual stage air filter (part number NV4074ST). With the pipe and air box opened up the jening in the dual carburetors had to be modified. A 122 main jet was installed in the secondary carburetor with the needle clip moved all the way to the bottom.. (Stock main jet is 108).ln the primary , ~ . ~ OTOBCYCL ANDATV EXPO "The largest public motorcycle show in the U.S." This year's show-goers will get an up-close look at all the 1985 touring, street and dirt motorcy<:les, as well as ATVs, accessories and apparel. Do your Christmas shopping and' enjoy the special demonstrations, shows and celebrity appearances all in one place - the Motorcycle & ATV Expo in Anaheim. November 16-18 Anaheim Convention Center • Friday, 5 PM-10 PM Saturday, NOON-10 PM Sunday, NOON-6 PM • Meet Bob Hannah and Donny Hansen I • See Bob Haro's & BMJI. Action's Trick Riding Teams • Special appearances by Angels Geoff Zahn, Ron Romanick and Mike Brown • Patricia McPherson of NBC's Knight Rider • Playboy Playmate of the Year appearances • Exotlc & Record-Breaking Bike Displays • Kawasaki "Bayou" 4-Wheeler Giveaway • Discount coupons available at local Nissan/ Datsun and motorcycle dealerships r-------------------------------, I $1.00 OFF COUPON '1 ~J:{[p@) I I I I I 1 i!Jlfi~ I I Bring this coupon to the Anahe.im Motorcycle & ATV Expo, November 16-18, and you'll receive $1.00 off .. . genera I ad miSSion pnce. - 1 I I ,I Only one coupon per person Produced by Hester Communications, Inc. uEP?cl ~ If, For information, call 714/250-8060.. L~------------------------------J Cycle News Ad Hotline 213-427·7433 --YAMAHA one per customer 20% OFF Parts Sale (with this ad) expires '2/31/84 * CITY CYCLE CENTER * 8423 Rosemead Blvd. • .. N. Downev ...._ _ 12131861-6217 12131861-5728 "";;:=:.1 25th Anniversary MILE HIGH ENDURO Cloudcroft. NM October 7. 1984 1st 250 A. GARY DAVIS KTM 250MXC 1st 0/A B. WOODY ALLISON KTM 250MXC 1st Open B. LARRY FEBERSTEIN KTM 495MXC 1st Over 40. TOM WAHLER KTM 420MXC @ JOIN THE TEAM For More Information and a Brochure. Write: KTM West 315 W. Bradley. EI Cajon. CA 92020 39

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