Cycle News - Archive Issues - 1990's

that he has been using the '93 frame in his race bike ever since, so Honda went back to the same settings for '97. However, we've com.pared figures of both the '93 frame and the '97 frame and haven't yet seen any similarities. "That's because it all depends where you take the measurements from (on the bike)," Honda's Bruce Ogilvie said. "A lot of times our figures differ from those from Japan, but I can assure you that the '97 geometry is the same as the '93 frame. Maybe not exactly the same, but very, very close." Here are the numbers we got at the first '97 CR250R intro in June: 28 degrees two minutes of rake and 116.5mm of trail. The frame isn't the only exciting new innovation with the new CR. To improve throttle response and pow.er, the CR dons a new power-jet-controlled (PJC) 38.3mm Keihin carburetor. The carb features a solenoid-controlled auxiliary main jet that opens at low rpm for a stronger, more linear response and closes back up at 8,000 r.pm for more overrev and top-end performance (leaner=faster). The factory Honda race team (among others, i.e. Kawasaki's Jeff Emig) has been using the power-jet carb this whole year. Rather than completely rehash all the technical.changes of the '97 CR250 (issue #26, July 3), we'll hit upon some of the other more significant changes. Suspension-wise, Honda went to a larger 47mm (up 1mm), low-friction Showa fork that includes an all-new dual-chamber cartridge design that separates air and oil with a rubber membrane to eliminate aeration. This design also provides more consistent damping and longer intervals between oil ·changes. The fork is equipped with 0.40 kg/mm springs. Ogilve says that Honda experimented wi th all kinds of different forks, even conventionaIs, and found the 47mm Showas to work best with the new chassis. Out back, the linkage system has a new ratio that is somewhere in between McGrath's '96 race-bike ratio and that of the '96 production CR250, and actually allows average riders to oCj:asionaJly bottom the shock. The '96 ratio did not, which prevented utilizing the rear suspension's full potential. The linkages mount to a new, radically tapered, 500gram-lighter swingarm. The shock has a 5.3 kg/mm spring and retains the highand low-speed compression adjuster that is a nice feature if you have the patience and skill to take the time and dial it in for your particular riding needs.. The motor has not changed all that much. It's basically the same as the '96 motor but with minor port-timing changes and a reshaped head for more liquid-cooling capacity. The piston did get a flat-top shave for '97, though, and the exhaust pipe is 34mm longer. Also, the reeds now have a lift of 12mm, 2mm higher than last year's 10mm. The CR also features a map-type digital electronic ignition system with an unusual feature that functions as a simple form of traction control. An eight-bit computer processor takes rpm readings 28 times a second. If the computer detects an excessive amount of engine acceleration within a preprogrammed range (an rpm spike produced when the rear wheel breaks loose) it will automatically retard the igition timing in an effort to contol the wheelspin. As a result, the CR is supposed to hook up better out of the turns and in slick conditions. When Honda firs't unvieled a preproduction version of the '97 CR250 to the press early June, Honda spokespersons said the first few production \;>ikes would be available for us (the press) to ride and evaluate in late August. However, shortly thereafter, it was announced that the production CR250 would be delayed for about a month and our first ride on the CR would not take place until October. Rumors about this delay began spreading like wildfire. We heard one rumor that the new frames were breaking; that tester Jeff Stanton, among others, was snapping the production frames in half. According to Honda technician Eric Crippa, this was not the case at all. Crippa did admit, however, that they experienced some cracking problems at the steeringstem area during early test sessions, but that problem was quickly resolved with gussetting a long time ago. However, the real reason the CR250 is late this year is due to incorrect suspension settings from·the factory. Earlier in the year, using American testers on U.s. tracks, American Honda came up with what they found to be the ideal suspension settings; then they sent those specifications to Japan to. be used in the '97 production CR250. Unfortunately, when the first batch of '97s arrived in the United States, the suspension on the production units came out a little stiffer than initially planned. As a result, American Honda chose . to delay production (for the U.S. mar· ket) until the factory got the suspension settings right. "When we mean settings, we don't mean just clicks (on the suspension adjustment screws)," Ogilvie said. "We're also talking about the internal suspension components - valve stacks, oil levels, spring rates and so on. We feel it was well worth the wait." The bike we now have in our possesion is identical to those that will be showing up on showroom floors soon, unlike some of the bikes already released in Japan and Europe with the original, harsher suspension settings. We'll tell you right off the bat that the new CR - aluminum frame, powerjet carburetor, computerized ignition .and all - will not suddenly shave 10 seconds off your lap times. We're not exactly sure if that's what we expected or not, but we can tell you that the '97 CR is a vast improvement over the '96 model. What really caught our attention the , first time we rode the bike wasn't so much the chassis, but rather the motor. No complete surprise here, though. After all, the CR's powerplant has been (Opposite page) The CR250R's frame mlgh be getting all the attention, but It's the motor that really caught our attention the first time we rode the bike. (Above) Just the fact Honda managed to build an ali-aluminum frame strong enough to handle the abuse of motocross Is a lechnologlcal achievement In Itself. Much of that technology came from Honda's road racing department. (Left) The new CR .tracts straight and true through .the stutters. (Below) The new CR250 gets a larger, one-piece radiator. the class standard for many years now. Perhaps the real surprise was that Honda managed to make the motor even better. As always, the new CR explodes off the bottom, but in a smooth, predictable fashion. Open up the throttle and the CR jus·t keeps pulling, pulling and pulling through an extremely linear powerband. Throttle response is immediate. Our bike, however, seemed to have a slight lean spot in the middle as we could detect a small amount of detonation down some of the long straights at the Honda track, where the elevation is approximately 2,200 feet. We swapped the stock needle for one slightly richer (half of a needle clip) and that was that. No more detonation, however miniscule it was in the first place. Even with the richer needle, our bike I;an just fine closer to sea level. As far as the "traction-control" ignition, well, to be honest, it's hard to tell whether or not it's really working. OJ;! the wide, sweeping turns, yes, the CR is easy to slide dirt-track style with the throttle pinned, but whether or not that has to do with th~ mind-of-its-own ignition or the super-linear powerband, soil conditions, tires or what, it's tough to decipher. But the bottom line is that the CR hooks up extremely well out of the turns; in other words, when you open 'er up, yo.u know what you're getting. There are no hidden surprises anywherein the pdwerband. When you first sit on the '97 CR, the first thing you notice is its rather level layout. From the back of the seat to the . front of the gas tank, the CR feels as flat as an ironing board. Combine that with

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