Top Mods For Your Kawasaki Off-Road Racer
Story By Trevor Hunter
Kawasaki’s dedicated off-road racer is the least changed from its MX brethren, yet in a lot of ways the KX450X is a better off-road bike than it is a motocross bike. The smooth power delivery works great in a lot of off-road scenarios, and the lighter handling chassis is easier to maneuver at slow speeds. Likewise, most everything about the bike is very neutral – nothing stands out glaringly bad and most all of its traits are good for the masses. However, it isn’t 100% perfect out of the box. Below are a few of the (fairly) inexpensive mods we found best fit for the Kawasaki. Some are for performance, some are for ease of use, but all have a purpose. We wanted to keep this list to more inexpensive, essential items only. Things like a suspension revalve or steering stabilizer can and do help on this bike, but are costly and will be talked about at another time.
The KX450X comes with a small tank, no handguards, and no skid plate. Right away, any serious off-road rider/racer will likely need and/or want these to be a little more off-road equipped. As usual, we went straight to IMS for a 2.8 gal fuel tank that’s also dry-break ready for when we need pit stops. The IMS tank installs easily, doesn’t affect the cockpit much, and adds over one gallon of fuel in a very clean manner. We’ve gone ~60 fast desert miles on one tank of fuel, but can stretch it out a little longer if the speeds are down. For those riding 45 minute GP’s, the stock tank generally does work for most riders, but the extra assurance and ability to go further with a larger tank is welcomed.
P3 Carbon supplied the skid plate and it has proven to be durable over the last 45 hours of use. We’ve had to replace the rubber grommets after ~40 hours due to wear and tear, and we had to replace one of the bottom skid plate bolts from a rock crushing in the allen head, but it has otherwise been bullet proof and protected the undercarriage and engine cases. Acerbis Handguards are a no brainer and keep the digits out of harms way.
A free bee! Similar to a lot of the “factory” off-road racers here on the West Coast, we dropped the forks to flush in the clamps. This helped find some stability at speed while also helping on decel. As we’d enter corners, the front end would want to at times tuck with the forks at their stock height. Dropping them flush helped this a lot, with both stock and revalved suspension. And when running stock suspension, it helped firmed up the action of the stroke when we felt it was too soft.
Gearing goes a long way on the KX and depending on where we’re riding dictates what gearing we run. Our go-to setup is 13/50 (same as the MX bike) and this works well on a motocross track and typical GP style course. The power spread is broad and spacing between gears is on point. In the desert, we drop down to a 13/47 or 13/48 to get the top end we need without completely killing first and second gear when needed in the technical sections. In the trees, a 13/51 or 13/52 allows you to chug down even more and stay off the clutch in slower terrain, although this new platform is much better at that than the old one.
We also like to run a one-link longer chain to get the axle further back in the swingarm. This helps with stability and the action of the rear shock, providing a smoother and calmer rear end.
Swapping out little things like the tires, bars, and grips help find more comfort in the KX. The stock AT81 tires are stiff and don’t always offer the best traction, especially up front, so going to an AT82 if you want to stick with Dunlop helps in that department (or whatever your favorite tire is). Lately, we’ve been running Maxxis’ MX-SI and MX-IH tires and have grown quite fond of them for their performance. Likewise, the Renthal Fatbar offers a lot of feedback to the rider, so we went with a Pro Taper CR Mid bend handlebar to remedy that issue. Lock-on grips can be tough on the hands in longer off-road races, though the stock KX ones are some of the best we’ve tried from ODI, but we prefer AME grips on-board and our hands thank us. To do so, we do also buy a Motion Pro Titan Throttle Tube (you can support DBT and buy through RMATVMC HERE) to replace the ODI grip/throttle tube combo.
A tip in the cap of Ride Engineering, their Wheel Spacers are a big plus. They don’t have a performance advantage on the track, but the stock wheel spacers hang in the wheel by a thread and fall out just about every time we go to put the wheel in place or pull the wheel off. The Ride spacers have a nice lip to them, staying in the groove and are near impossible to come out of place in wheel changes. Whether you’re changing wheels in the race or simply in the garage, these are nice to have and worth every penny. You can buy the FRONT Spacers HERE and the REAR Spacers HERE.
DT-1 Filters sent us their screenless cage and domed air filter setup. Similar to the pipe but not as drastic, it gave the bike better puller power from top to bottom and increased throttle response.
Different from the ’24 bike, we now have a Pro Circuit Ti-6 full system on the bike. The power delivery is quite different between the two exhausts, and we’ll have a more in-depth comparison on them, but in short, the PC exhaust has a more aggressive power delivery.
The KX is a very good off-road race bike – dare we say one of our favorites – but a few mods can go a long way on this machine. Stay tuned as we put all of the pieces of the puzzle together on the complete package we’ve settled on for our KX450X Project Bike.
