Last year, Kawasaki totally redesigned its two-stroke motocross machines, including the KX250. Take a look at our discussion of the 2003 model, and note the changes, particularly, to the chassis. For 2004, Kawasaki didn’t rest.
Kawasaki dove into the KX250 engine for 2004, and made extensive changes . . . basically to improve power delivery everywhere, from bottom to top.
- An increase in compression is intended to improve low-to-mid power, which was the same purpose for filling in last year’s intake sub-ports on the cylinder.
- Scavenge and exhaust ports were raised for 2004, to improve mid-range and top-end performance.
- Kawasaki also changed its KIPS power valve for 2004, to provide better sealing for more low-end to mid-range performance.
- Even the exhaust pipe and the intake air duct are changed. The pipe is said to improve mid-range to top-end power, while straighter air passage from the air filter through the carburetor and into the engine is intended to improve throttle response and power from bottom to top.
- A little weight was removed from the crankshaft, which should allow the 2004 KX250 to rev a bit quicker.
- Lots of chassis tweaks were made for 2004, but here are the highlights. An all-new rear suspension linkage system now anchors the Uni-Track link in the swingarm, instead of anchoring it to the frame. Overall, the rear linkage system is said to improve traction and allow for a lighter frame, because certain suspension forces are no longer transferred directly to the frame. The swingarm is 2mm longer for 2004.
- While the forks are still 48mm Kayaba units, they are a new, semi-sealed cartridge design, and carry redesigned fork guards.
- The front brake line is now routed directly to the caliper, rather than wrapping under the bottom of the fork (a similar design to Honda’s). Slightly higher foot pegs, and a raised rear brake lever improve ground clearance and work in conjunction with an 8mm higher seat for improved ergonomics.
After riding the KX250 extensively, with riders of all skill levels, we can confidently state that Kawasaki has a very competitive 250cc two-stroke machine for 2004, with some unique qualities.
First and foremost is the KX250 engine. Those engine changes and refinements described above have led to a much more linear power delivery (yes, even more so than last year) that is so smooth it is almost four-stroke like. It is also plenty potent, particularly, in the mid-range.
With a strong, but smooth pull off the bottom, the KX250 quickly reaches its beefy mid-range and then revs a bit farther than last year on top. Overall, the powerband is fairly wide for a 250cc two-stroke, and very effective. The bike hooks up very well, and requires less throttle precision than some of its competitors.
Overall, that broad powerband comes on so smoothly that it feels like the KX250 has a heavy flywheel, but it really doesn’t. The bike can rev pretty quickly. The engine makes the KX250 not only a competent motocrosser, but an excellent choice for an all-around machine (motocross and off-road — including enduro/trial riding).
While the KX250 has a very good motor (perhaps, one of the best 250cc two-stroke motors ever for novice motocross riders and off-road riders of all skill levels), it is in the handling department where the KX250 really shines this year. The perimeter frame (redesigned last year — see above) offers a great combination of stability and turning ability. Indeed, the frame was slightly modified to improve turning this year, and the KX250 still has its legendary stability on high speed, rough straightaways.
The new rear linkage design helps with hook-up over acceleration bumps, and also seems to keep the rear end from kicking on sharp, square edged bumps. The stout, 48mm fork is plush, overall, but a little harsh mid-stroke (something we never completely dialed out).
The front brake on the KX250, now routed like a Honda (directly to the caliper), has a very firm feel at the lever, and great power. Feedback from the front brake is decent, but not at the top of the class. Definitely a good front brake, however, and a huge improvement over the mushy front brake Kawasaki was known for a few years ago.
The transmission shifts with a bit more resistance than some of those found in rival manufacturer’s bikes, but it shifts very positively (which is more important), and handles up-shifts under a power load pretty well.
The ergonomics of the KX250 have changed from last year (see above), and we would agree they are an improvement for most riders — providing more room between the seat and pegs, and an even flatter seat. The KX250 again features reversible bar mounts that allow the rider to place the bar in one of two positions, either closer or further from the rider.
All-in-all, Kawasaki has built a very versatile bike with the 2004 KX250. A snappy, two-stroke motocross machine that is effective on the track, is also so smooth in its power delivery, and handles so well, it can be used for virtually any type of off-road riding, and is easy to ride (remember that “feels like a four-stroke” comment?). Is it the most powerful motor in the class for 2004? Probably not, but it might be the most effective weapon for novice motocrossers.
The 2004 Kawasaki KX250 retails here in the United States for $5,899. Take a look at Kawasaki’s web site for additional details and specifications.
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