Photos by Adam Booth

After months of speculation, the 2013 Kawasaki KX450F is finally here. As expected, Kawasaki continues to innovate with a handful of changes to their 450 motocross machine, all of which help take this bike to an even greater level of performance and help keep it on par with the rest of the class, particularly the heavily-revised Honda CRF450R. We are in the middle of two days of initial testing the new Kawi at the beautiful Zaca Station MX track, and are already getting a good feel for what makes this bike tick.
For 2013, the Kawi 450 receives a Kayaba air fork that utilizes pneumatic technology to provide better damping and control, thus saving weight by doing away with the main fork spring. The setup is pretty cool; 35 PSI is standard, and dropping or adding just two pounds of air is equivalent to changing a spring rate. As with the Honda, the forks are adjusted via small valves at the top of the fork cap, although the Kawasaki’s KYBs do not feature a built-in shrader valve. Having already tested the pneumatic fork technology on the Honda, Dirt Rider’s main testers already seemed to be adapting to the ins and outs of the new setup.

Along with the fresh fork, the bike also gets a handful of internal changes—most notably to the piston—and still features Kawasaki’s Launch Control technology. The Digital Fuel Injection has been slightly revised, and several DFI maps are also available and can be changed without the use of a personal computer via two additional couplers that come with the bike—one for “standard” use, one richer “hard” setting for slippery conditions, and a slightly gnarlier “soft” coupler for deeper loam. On the chassis front the swingarm has been lengthened slightly, while the shock sees a few minor tweaks including finer rebound adjuster settings. The grips are new and longer, and the front fender and number plate are totally new. The rear brake rotor has also been changed, along with the front brake master cylinder. A number of other minor revisions round out the list of changes to the bike, which still looks as stylish and aggressive as ever.
On the track, the KX450F definitely has a race-inspired motor. The bike snaps extremely hard off-idle, so much so that it can cause you to blow out of your line if you’re not careful. The acceleration is strong and constant throughout the lower portion of the power, while a peppy mid-range gives this machine a powerfully usable spread of meat right in the middle of the revs. The top end pull is incredible, although the rev limiter on the bike does exist and can be hit if you’re not careful. Shifting is flawless and clutch action is decent, with good feel and a consistent engagement point. The big Kawasaki is still noticeably loud on the track with a slightly raspy note, although our experience has been that aftermarket exhaust remedies these traits immediately. The bike starts fairly well if you give it a smooth kick, and the tuning (formerly jetting) was clean, although slightly lean and poppy in stock form at the Zaca Station track.
The air fork feels noticeably different from the Honda’s in that it features a cushy initial portion of the stroke that leads into a fairly firm mid-stroke; heavier riders will love the bike’s ability to maintain its stance here, while lighter guys may opt for less air to make the ride more plush. When pushed, the bike will settle into the mid-stroke, although bottoming resistance is excellent and blowing through is not a concern unless you really, really mess up. In these rare instances, the bike can get a brief bit of headshake due to the immense load placed on the front Bridgestone, although this only occurred a few times throughout the entire day of riding. Overall, the fork held up well and the front to back balance of the bike was incredible and definitely felt improved (read: less sensitive and tough to set up) compared to last year. The KX450F’s shock is a good match to the front fork and was generally very compliant on bumps and chop, with only a few adjustments to the clickers needed to set the bike up for the way the track was for us.
The ergonomics of the Kawi are comfortable; we moved the four-position bar clamp around to try to open up the cockpit a touch, but ended up going back to stock and rolling the bar forward a tad. The bike feels somewhat long and tall at times, though not overly weight and still maneuverable in the air. Changing lines in turns was a snap, and all of our testers were surprised by how well the KX450F can stick to an inside and gain traction while on the shoulder knobs of the tire. Rutted turns were just as effortless as flat corners, with the suspension settling well into the stroke and allowing the bike to grab exciting straight-line traction upon corner exit.
Shootout season is nearing, and as we get closer we’ll continue to put more time on the KX450F, along with the other 450cc MX machines. As always, please head on over to the facebook.com/dirtridermag page if you have a question that you’d like us to answer, and stay tuned to the October issue of the magazine for a full test on this motorcycle.
Want more? Check out another first impression on the bike from our pals over at Motocross.com: First Ride with the 2013 Kawasaki KX450F. Also, see specs for the 2013 Kawasaki KX450F below.
| 2013 Kawasaki KX450F Specifications |
|---|
| Engine | Liquid-cooled, four-stroke single with DOHC and four-valve cylinder head |
| Displacement | 449cc |
| Bore x stroke | 96.0 x 62.1mm |
| Compression ratio | 12.5:1 |
| Fuel Injection | DFI® with 43mm Keihin throttle body |
| Ignition | Digital DC-CDI |
| Transmission | Five-speed |
| Rake / trail | 26.9 degrees / 4.4 in. |
| Front suspension / wheel travel | 48mm inverted, Kayaba PSF with DLC coated sliders, 22-position compression and 20-position rebound dampening adjustment / 12.4 in. |
| Rear suspension / wheel travel | UNI-TRAK® linkage system and Kayaba shock with 50mm piston, 22-position low-speed and stepless high-speed compression dampening, 33-position rebound dampening and fully adjustable spring preload / 12.4 in. |
| Front tire size | 80/100-21 |
| Rear tire size | 120/80-19 |
| Front brake | Single rigid-mount 250mm petal disc with dual-piston caliper |
| Rear brake | Single 240mm petal disc with single-piston caliper |
| Overall length | 85.8 in. |
| Overall width | 32.3 in. |
| Overall height | 50.2 in. |
| Wheelbase | 58.3 in. |
| Ground clearance | 13.0 in |
| Seat height | 37.6 in. |
| Curb weight | 248.0 lbs. |
| Fuel capacity | 1.64 gal. |
| Color | Lime Green |

