Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/126608
BUdget bettennent Improving the fun quotient on Suzuki's DR500Z By Karel Kramer When Cycle News had Suzuki's DR500 th urn per in for an impression several weeks ago, we were highly impressed with the bike's fun quotient, but were less impressed with parts of the bike; those parts being the ones that held the w h eels up . The frame seemed to perform quite well 22 until the sus pen ders reached their lim its. With the su spension bottoming madl y, the bike just wallowed lik e th e wheels and frame were tak ing th e shock in the form of flex. It never spi t a rider off , but both th e bike and rider took some pounding. Wh en we began to diagnose the problem, we found that there were onl y a few parts that wer en't doing th eir job and a couple of them were n ormal replacement item s anyway. Probl em number on e was th e rear shocks. T hey had too much compressio n da m pi n g an d not eno ugh sprin g so they felt h arsh o n sma ll bumps and soft on big ones. We put a $300 ceili ng on the hopup, which is a lot, bu t sti ll a sma ll eno ug h amount to make th e DR an attracti ve package if the money would bring out the excell ent bike hidden under the flaws. With that kind of a ceiling, and because we wer e trying to build a great trail bike rather th an a racer, we had to look in the budget shock market. Fortunat ely there are several good shocks to choose from in this area. Both Moto-X Fox and Works Performance still sell versions of an older design shock that work well in this application and are rebuildable. Fox spring shocks and Works "oilers" are both available in the $125-150 range. S&W sells a freon cell shock in the same range that has been proven , but is not rebuildable. Works Performance sets th e shock up for your pe rsonal needs, Fox g iv es yo u a cho ice of damping and du al rat e sp ri n gs .and S&W gives yo u a ch oice of dual rate sp ri ngs. We decided to go wi th th e Fo x shocks and simply called Fox and told them th e year and model bike and how heavy our riders were. They sent u s a pa ir o f stock length 16" firm shocks for $1 19, a number 165 blue spring set for $16.50 a nd a pair of soft white sp rin gs for $7.39. They came with a n assortment of shock bushings an d went on with virtually no hassle. The second ar ea that seemed to warrant immediate attention was the front suspension. Its overall action seemed fair enough, but we checked. around for a fork kit and couldn't find any that didn 't extend the travel. We chose not to change the travel in the front or the rear since first of all, the geometry seemed close and we didn't want to mess with it . Secondly, a motorcycle that weighs in at around 290 pounds wet doesn't need to reduce the slider overlap on 38mm forks. We felt we would lose in flex whatever we gained in travel. We drained the forks and refilled them with )0 weight Kal-Gard smooth stroke oil, which has Mol y in it and is very slippery. Some people have had problems with seals not being able to ho ld the stuff, but it has improved fork ac tion on bik es we hav e tried it on a nd leakage sho u ldn' t be a problem with good sea ls. T o make the forks sti ffer at th e bottom of th e stroke, we raised th e oil level in the forks . To do th is, raise the bike off the ground so that the wheel is o££ the ground. Drain the stock oil and replace th e drain screws. Pour the recommended a mo unt of oil in to the fork s with the caps o££ and the springs out. Stroke the fo rks up a nd down until th e sq u ish in g noises stop emanating from the fork tubes. Wh en th ey stroke up an d down quietl y, all the ai r trapped in th e oil and th e forks has been wor ked out. Wi th a special syri nge or a n or dinary steel rule, bottom the forks and measure th e o il height in the tubes. The oil sh ould be aro u n d six and a ha lf in ch es from th e to p of the tube. Add oi l until it is. Rep eat the air purging operation, p ut the springs back in an d go take a test ride. About 5-)0 pou nds of air will p ro bab ly need to be in the for ks si nce the springs are still too soft ini tiall y. Air press ure shou ld be checke d with the wheel o ££ the groun ds. Perhaps sp ri ngs from a n 'SO model RM 400 wo u ld cu re th is. If you r fork s are fine over small bumps but h arsh on bigger ones, then low er th e o il level until th ey bottom as often as su its your riding style. Forks th at never bottom are too stiff. T he last must cha nge item is th e tires. T he DR co mes wi th the same front tire as the R M125 an d a sim ilar rear ti re that is larger. They simply don ' t have th e side wall and knob strength to perform on the DR . O ur front tire started to show severe signs o f wear on th e side kno bs before the middle o nes o n th e fro nt, a sign that the kn ob s are folding over u nder cornerin g loads. Repl ace th e stock tires with a more su bsta n tial set o f tires with stiffer sidewalls. We considered the tires a normal wea r item so we had a few bucks left in the budget. We figu red we wo u ld try to lose a litt le heft as the shocks had already dropped the wei gh t a co uple of poun ds. We called Pr oT ech an d got o neof their su per-ligh t exha us t p ip es. T he pipe was th e onl y product that got mixed review s, and th en onl y because, as we said at th e outset, we were going for a trail bike. It d id make th e bike pull better, but for a tra il bike th e noise was a bit much . Pro-T ech says it is a performance pipe a nd we would give it a hearty recommendation for racing because it tu cks in perfectly, fits well and works. For tra il riding we prefer a quiet bike and the weight savings of approximat ely six pounds was not too no ticeable. The bottom line is how did it work? G reat . Before Suzuki pried th e bike away from a tearful editor, we tried some sandwas h whoopdies with much great er co n trol. The bike's weight is noticeabl e only when yo u get stuc k so mewhere and have to move it by hand. jumps and other obstacles, including a couple of surprise ditches, were handled with ease. All four testers , including an AMA Pro, loved the bike in the hills. For play riding we think that a DR500 and some carefu lly spent money will provide one of the best possible com• binations. Moto-X Fox 520 McGlincy Lane Campbell, CA 95008. 408/371·1221. Works Performance Products . 8730 Shirley Ave. Northridge, CA 91324. 213/701-1010 , SIlcW Engineered Products, Inc. 2617 Woodland Dr. Anaheim, CA 92801. 714/527·1641. Pro-Tee 282 Gemini Brea, CA 92621. 213/697 ·6759. -