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Issue link: https://magazine.cyclenews.com/i/126786
Johnson's bike is a blast to ride. The harder the bike is pushed, the better it works. The forks are incredibly stiff - almost rigid. progression. johnson likes his forks incredibly stiff. For example, the stock spring is rated as a number .300, while the optional heavy-duty spring from Yamaha is .325, which is quite stiff. johnson iJses a .375 spring. At the beginning of this year -and throughout previous years - Johnson and his teammates have had problems with the rear wheel collapsing on rough tracks. The technicians at Yamaha thought they had the problem solved with the new Zspoke design; however, johnson, who is known to destroy rear wheels often, managed to collapse the Z-spoke wheels. After breaking a wheel during the second National, Johnson switched to a standard, heavy-duty spoke design YZ490 wheel and the problem disappeared. Yamaha decided to use this wheel, at that time, on the 'S5 production Yamahas, but then they developed a stronger, revised Z-spoke wheel halfway through the season. Since the points race was tightening up, Johnson and Leu opted to stick with the already-proven YZ490 wheel, not wanting to take any chances. Keith Bowen, however, did make the switch and had no problems. The new 7;-spoke wheels with gold Excel rims will come stock on 'S5 YZs. Since Johnson uses a 490 hub, the brake drum is larger on- his bike than .on a stock 250. Up front, Johnson uses a disc brake system that will be found on 'S5 production YZS. Most of the other changes are relatively minor ones to help make the bike more reliable, or to satisfy Johnson's personal preferences. The radiators are reinforced with stronger brackets; the bottom frame tubes are flattened for strength and the rear brake lever stop is beefed up. To hel p prevent flats, heavy-duty inner tubes from Dunlop are used along with a Pro Flo air filter and a stronger TR DJ.D. chain. Instead of the usual 50/50 mixture of distilled water and coolant in the radiator, Lett uses more coolant at a 80120 ratio. Yamaha R synthetic oil mixed at 40: I supplies lubrication. Lett built his own chain guide out of very hard plastic. He designed it so the part that the chain actually slides on can be replaced wi thol,l t having to replace the whole chain guide, which has to be done on the stock YZs. The handlebars are custom made for Johnson by Answer Products. The johnson signature bars are now available to the public. He uses short levers on both the brake and clutch sides, and the clutch lever actuating arm on the engine was extended for a lighter pull. An aluminum shift lever was custom built for johnson, because he has such large feet - it was lengthened Smm. johnson uses slightly modifed Honda grips. Every week Lett tears the bike down to the bare frame, splits the engine cases and checks everything for wear. Lett replaces the rings after every race and the piston after every rwo races. The frame is original and has never had any cracks. Now the fun part - riding it. After 10 Nationals, and untouched after thefinal race at Washougal, I thought Johnson's bike would feel a bit beat up - I was wrong. The controls felt as though the bike came right out of the crate, but the most impressive part was the motor. Throttle response was very crisp. Through the gears, the power came on quick and strong; there was no hesitation anywhere throughout the powerband. Each gear revved out very quickly, so it felt as though it had to be short-shifted. Compared to a stock YZ250L, Johnson's Yamaha felt more like a 125 with double the horsepower; however, it wasn't hard to ride at all - in fact, it was easy. The. main power advantage over a stock YZ was on top. A stocker has plenty of grunt down low but lacks on top; Johnson's has about the same power off the bottom but keeps pulling when the stocker starts to sign out, but it does have to be shifted sooner. Even though the track was hardpacked and dry, Johnson's bike was easy to control exiting turns. The longer rod and different ignition makes the power delivery very broad and manageable. It rarely wanted to fishtail out of the turns (Bridgestone tires were mounted). The most impressive aspect of the motor wasn't the top speed, but the strong and Johnson trashed the stock Z-spoke wheel for a standard-spoke YZ490 wheel. Next year, YZs will have new revised Z-spoke wheels. Forks are equipped with a Simons Anti-Cavitator fork kit. Disc brake will be stock in '85. smooth powerband. It hooked up well and was very predictable.' In tight turns, one flick at' the clutch lever brought the mid-size rocketship to !ife, no matter how low the revs dropped. The motor was juSt plain neat! Although much better than stock, the overall suspension package didn't quite fit my tastes - mainly beause of the forks. Stiff doesn't really describe how they feel - it's more like rigid. My arms rarely pump up when riding or racing, but after two quick laps, they felt like they were going to explode. According to Lett, even Glover's and Bowen's forks are much softer than Johnson's. Braking bumps felt the worst. The forks felt as though they only had two inches of travel instead of 12; it is definitely a rough ride. John.son likes them stiff so he can really push the bikes through rough terrain and over huge whoops as hard as he can, and he doesn't like the front end to dive when entering turns. The back end, however, was quite nice and wasn't nearly as stiff. Johnson weighs about ISO pounds, while I ' weigh in at about 155; I felt the rear end was about right for me. The biggest complaint I t'!ave about the stock YZ rear suspension is that it's way too soft and pringy - johnson's wasn't. It was stiffer which gave me much more confidence when the going got rough. Nonetheless, suspension tun·' The porting specifications used are the same ones revealed in the Wrench Report. ing is the rider's personal preference - what might be right for him, won't be right for anyone else. Slowing the Yamaha down was an easy task. The front disc brake worked very smoothly and didn't have any tendency to lock up even on the slick stuff. The rear brake worked almost as well, and it too didn't like to lock up. As the day progressed, I felt more at home on the Yamaha; enjoying every second on it. I started to feel qui te fast on it, much faster than on a stD9< YZ. The bike liked to be pushed, and the harder you pushed it, the easier it was to go faster. It loved to be slammed into the berms and sailed over the jumps, but my endurance was too short on the YZ. The stiff forks quickly wore me out. Then it was time to load up, and the next stop was Yamaha headquarters in Stanton, California. There, Lett tore down the bike and proved to me all the modifications were for real. The only real bummer about johnson's Yamaha was that it didn't turn me into a National-caliber rider. But I sure had fun trying. Anyone could own a Rick johnson replica YZ250L because his Yamaha came off the same assembly line as Joe Blow's YZ . sitting next to you on the starting' gate. However, to modify a produc· tion YZ like Johnson's would cost money - but at least you've got the choice. • 17