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/128372
The X's slipper-type two-ring forged aluminum piston, Nikasil cylinder lining, 12.0: I compression ratio and 40mm FCR Keihin carburetor, with a throttle position sensor (TPS), have all been carried over from the 'OS motocrosser, as is the X's unique lubrication system that hosts oil in two separate chambers - one for the clutch and transmission, the other for the engine (crank, cam piston and rods). This design has many benefits: It keeps potential transmission/clutch contaminants from entering the cam and crank area, it allows oil to be specially designed for specific jobs, it provides for a more stable temperature environment, it permits the use of a smaller pump and oil pan for reduced weight, and it eliminates power-robbing oil drag around the crankshaft. The downside? When changing the oils, you have to deal with two drain plugs and two different types of oils. You don't want to get the two oils confused, bad things will happen. Important: Read the manual') Here's the gist: The engine (left side) gets the oil with moly, and the tranny/c1utch side (right side) gets oil without moly. Speaking of oil, high engine-oil consumption has been an issue in the past with the CRF-Rs, especially the smaller 2S0, but Honda says they've conquered this problem by deleting an oil hole in the piston, which they claim reduces oil consumption by two-thirds. To monitor oil usage, the X employs a dipstick rather than a sight window like the R's have. Engine overheating is always an issue when it comes to serious off-roading, so Honda increased the X's cooling capacity by nearly 10 percent via larger radiators. Plus, the radiator catch bottle has been relocated behind the skid plate, which helps lower the bike's center of gravity. The X's exhaust system is, as you can imagine, very different than the R's: The head pipe is longer, droopier, and smaller in diameter, and, much like your car's muffler, the X's aluminum mufOer is purely mechanical, meaning there is no packing material in there. The muffler, of course, is eqUipped with an USFS-approved spark arrester and emits just 90.0 db. Slow-speed tractability is, as you know, an off-road rider's best friend, so Honda addressed this issue by adding more mass to the AC generator and flywheel. A wideratio five-speed transmission, which features beefier gears than the R model, transfers power to the rear wheel. Compared to the R's gear ratios, first and second are geared lower, fourth and fifth are geared taller, and third is geared the same. Externally, the X comes with a S I-tooth rear sprocket, versus the R's 48. The X uses a T-ring sealed drive chain, which is narrower, lighter and stronger than conventional a-ring chains. The X also gets an electric starter. It is, however, significantly different than the 250X's starter in that it is both smaller (5 Imm vs. 62mm) and 6 ounces lighter. This was achieved by switching from standard ferrite (iron) magnets to more power- ful rare earth (neodymium) magnets. A kickstart mechanism is still retained for backup purposes, and there's an automatic decompressor system to simplify the starting drill. A hot-start lever is mounted to the dutch perch. CHASSIS-WISE Like with the 2S0X, a lot of head scratching went into the 450X's chassis and suspension, the main goal being to make the bike more compliant for off-road use - something the moto 450 will never be. The fourth-generation aluminum twin-spar frame incorporates the same overall design as the 450 motocrosser but has been reengineered and tuned specifically for offroad use. Very few pieces carry over between the frames of the two 450s. In short, Honda actually designed in a bit more flex into key areas of the X's frame. Uke the motocrosser, the X gets the Showa twin-chamber cartridge fork that offers 16-way compression and rebound damping adjustments, and it features the same low-friction honing treatment as the works bikes. However, there are important differences between the X fork and the R fork. To achieve a different flex character better suited for the trail (i.e. less deflection), the X gets triple-taper outer fork tubes, whereas the R has double-taper units. Plus, even though the X and Rshare the same .4 7 kg/mm spring rate, the X's fork has been revalved for a softer initial stroke. In the back, the ultra-adjustable Showa damper is pretty much the same as that found on the CRF but is revalved and rides on Pro-Link linkages unique to the X, as is the swingarm, which features a dual-axis, double-taper design and a stout castaluminum crossmember. The X gets an 18-inch rear wheel, of course, and Dunlop tires, but both wheels share the same lightweight hubs and aluminum spokes as the CRF450R. The front wheel also gets a larger-diameter axle and a wider wheel bearing for improved rigidity. Braking is handled by 240mm discs at both ends, with a dual-piston caliper up front. Climbing aboard, you'll notice a wider seat than on the CRF450R, with more rounded edges and a nonslip cover, which wraps around a new multiple-density foam designed with long-distance riding in mind. You will also see an adjustable odometer, aluminum Renthal 971 handlebars, a quickadjust clutch perch, and a larger fuel cell that holds 2.27 gallons. (The R holds 1.9 gallons.) Lighting your way is a 35-watt halogen "slim-line" headlight, and in the back is a hardly noticeable LED taillight that is intergrated into the rear fender. The CRF450X also grew a kickstand. Last year on the 250X, Honda found out that it wasn't a good idea to mount the kickstand to the frame, as it caused handling issues. So for '05, Honda integrated the kickstand with the left footpeg mount, and it can easily be removed if so inclined. ALL ABOARD If you're used to riding the CRF450R, or the king of the big-bore four-stroke off-road class, the KTM 450 EXC, the 450X will feel a little on the large side, mainly because of the slightly wider seat and tank. And it feels just a tick wider (more toward the front of the seat than in the middle) and taller than the Yamaha WR450F. Otherwise, it's just as comfortable as the CRF450R - typical awesome Honda ergos. Seat height might be little tall for some, but if you're in the upper 5foot range, you'll fit just fine. We weighed both the CRF450X and the Yamaha WR450F, and they both tipped the scale at 259 pounds, without gas. Currently, we don't have a KTM 450 EXC in our possession, but we do know that it is about six or seven pounds lighter than both. Push the button and the X qUickly fires to life, and it is nice to know that a kick lever also comes along for the ride, just in case the battery dies, a wire snaps or something goes wrong with the electrics. Noise is certainly not an issue with the X; it is very, very quiet, yet still sounds like it means business. Power comes on nicely off the bottom. It's not an exceptionally hard-hitting machine compared to the 450R, but it does pull with authority when you grab a handful of throttle. Midrange is where the Honda really comes alive and things only get more exciting after that. The 450X is downright fast, but what impresses us most is how the machine lugs off the bottom. When the going gets tough, the Honda's motor chugs along nicely and resists stalling, but it is still a good idea to keep a finger close to the clutch. A very low first gear helps make the Honda remarkably easy to CYCLE NEWS • ':'0" L ~ ~~'~5 29