Husqvarna FX450 Off-Road Race Bike Build

February 26, 2019 / by Kevin Bailey

Wiseco Powersports Marketing Coordinator Kevin Bailey out of Wiseco's CA office grew up riding and racing off-road, first swinging a leg over the bike at four years old. Recently, he purchased a 2017 Husqvarna FX450 and set out polish it up for a great off-road race bike package. See all the modifications and products the Husky received here.

In today’s social media-driven world, there is no shortage of bike builds, race photos, and dirt bike videos for us to watch. Most of the dirt bike publications are pumping out project bikes, including everything from restorations, to modern bikes with works parts, to custom-fabbed AF builds. However, what we don’t tend to see are a lot of off-road builds—and builds that are actually attainable by the general consumer, for that matter.


The Husqvarna/KTM platform was chosen simply because it felt like it did everything well. Where other brands seemed to have some trade-offs, the orange and white bikes seemed to be the complete package. The bike corners well, feels stable at speed, has good power, and feels very light and nimble. It almost took some getting used to because it was so easy to ride.

But, why the Husky over the KTM? The reason was simple; it looked cooler.

While the bike is an awesome package from the factory, we all know it’s near impossible for dirt bike guys to leave things untouched. The bike is ridden primarily in the varying off-road desert terrain of Southern California. So, the bike received some modifications and bolt-on parts with the ultimate goal of a reliable, fast and fun off-road machine.



One of the first things that was addressed after purchasing the bike was protection. There is no skid plate installed from the factory, so the cases were very exposed, just inviting a rock to punch a hole through them. It was enough to make someone nervous even riding on the motocross track.

Cycra hooked up the FX450 with one of their Full Armor skid plates. This is a thick plastic skid plate that can be easily removed and replaced and stands up well to the elements of off-road riding. The Husky blue color option is a cool touch as well.

The Cycra Full Armor skid plate protects the cases, water pump, and the ignition cover.

One of the downfalls of the Huskies and KTMs is how far the stock linkage and shock clevis hang down. When looking at the side profile, it seems scary-low when thinking about riding through the rocky terrain of the California high desert. An impact on the clevis could lead to a bent shock shaft, which is not a cheap fix.

There are multiple options for linkage/clevis guards for these bikes, but the Fastway linkage guard by Pro Moto Billet seemed to be by far the best combination of functionality and protection. It’s a complete, one-piece billet linkage arm with a built-in guard that sits in front of the shock clevis and linkage knuckle. With this setup, if there’s an impact on the guard, it gets distributed evenly across the linkage arm instead of focusing on the shock clevis/shaft. Plus, the composite guard plates are replaceable.

The Fastway linkage guard by Pro Moto Billet is a single-piece guard that takes place of the stock linkage arm. This guard is much cheaper than replacing a shock shaft.

This linkage also offers different inserts to adjust the length, but it was kept at the stock length in this build.


The bike came with two preset maps, one ‘mellow’ and one more aggressive. For an experienced rider, the mellow map feels just that—a little too mellow. The aggressive map is fast and responsive, but still not quite as aggressive as some factory maps from other manufacturers.

To achieve more responsiveness, quicker revving, and an overall more powerful feeling, the stock piston was replaced with a Wiseco Racer Elite piston. This piston’s combination of asymmetrical skirt design and lapped compression ring provided even quicker revving and reduced the blow-by substantially. As a package, the increase in power, especially on the bottom, was impressive, and made the bike even more of a blast to ride.

The FX450 was fitted with a Wiseco Racer Elite piston which helped provide quicker revving, less blow-by, and a more powerful feel through the whole power range.

Find Wiseco pistons for your machine here.

Another major component that was replaced was the clutch system. Being an off-road focused bike, Rekluse’s latest auto clutch technology was the immediate desire. The bike received a Rekluse RadiusCX clutch setup, which includes their TorqDrive clutch fibers, Core billet components, the EXP 3.0 disk, and an adjustable, billet slave cylinder.

Rekluse's RadiusCX auto clutch is the ideal candidate for an off-road package.

This clutch package uses the stock KTM clutch basket because they’re steel and very durable, but all other internal components are replaced. The inner hub, pressure plate and clutch cover are all billet and hard anodized, and the TorqDrive fibers do a great job of improving torque transfer from the engine to the rear wheel. Once installed, this auto clutch system is adjusted by simply turning an allen bolt on the slave cylinder.

The clutch's free play gain, a critical measurement of the auto clutch, is adjusted via an allen screw on the billet slave cylinder.

Riding with the RadiusCX has been like cheating. It makes an amazing difference when riding through technical off-road terrain, especially if it’s later in the ride/race and you’re getting tired. You can lug the bike in first or second gear over anything without touching the clutch lever and not have to worry about stalling.


To round out the upgraded engine package, a Pro Circuit Ti-6 complete exhaust system was installed. For some reason, the stock Husqvarna muffler is more plugged up than the KTM, so the exhaust made a very noticeable difference. The bike grunts hard off the bottom and pulls strong in the mid-range. Plus, the system has a removeable spark arrestor, which is critical for OHV areas in California.

Pro Circuit's Ti-6 exhaust system gave a noticeable increase in throttle response and torquey-ness. Plus, having a 3 piece system allows you to remove it without taking the shock off like the stock exhaust.

Complementing the exhaust system, the FX450 inhales through a ProX dual-stage air filter.


The final power delivery is transferred to the rear wheel via a set of ProX sprockets and gold ProX chain. The rear sprocket is hard-anodized steel, so there shouldn’t be any worry of having to replace it any time soon.

ProX chain and sprockets have a great track record of lasting through tough conditions, perfect for off-road riding and racing.


Suspension is a component that’s always been more than just something nice to have, it’s a safety factor. The forks and shock were re-valved and set up with a GP spec by Cloverhill Racing Services out of California. The shock spring rate was also increased to match weight and riding ability.

Cloverhill Racing Services worked their magic on the stock forks and shock, setting them up with a GP spec for a specific rider weight.

A lot of people feel the WP AER48 forks are the best production air forks out there, which is why they were kept air and not converted to spring. However, because this bike is a 2017 model, the forks did not have the updated mid-speed valving components in the damping fork, causing the forks to tend to blow through the middle of the stroke. Cloverhill replaced the stock mid-speed setup with one from a KYB spring fork, which actually includes a shim stack, an improvement over stock components.

Bottoming resistance and the mid-stroke of the forks was greatly improved after Cloverhill's modifications.

The difference after the suspension work was great. The bike tracked much straighter and soaked up the big whoops and g-outs more effectively, especially at speed. The bottoming resistance in the forks was a huge improvement and contributing factor to the overall handling improvement as well.


In the controls department, the Husqvarnas come stock with Pro Tapers and ODI lock-on grips. ODI set up the bike with one of their new colorways of the MX V2 Half-Waffle. The grips are very comfortable to ride with, last a long time, and are insanely easy to change out. No more scraping old grip glue off with a razor blade will make you a customer for life.

ODI lock-on grips are game changers if you're used to the old grip glue method.

Wheels & Tires

The stock wheel package on the bike included billet hubs and matte-black D.I.D Dirt Star rims, so, well enough was left alone. Because the FX450 is the off-road race model, it comes stock with a set of Dunlop AT 81s, the rear wheel being 18” instead of 19”. Dunlop makes good tires, but these seemed to wear out fast and are not cheap to replace. So, the stock wheels got wrapped in a set of Tech 2 Pros from STI tires. These tires have been insanely impressive. Handling feels good and the rear tire holds up very well, even to rocky conditions. Plus, the price point is more than fair compared to what else is out there.

The STI Tech 2 Pro tires have performed and lasted beyond expectations. They are cheaper than many of the major brands, and they stand up very well to the harsh terrain of off-road.


The stock seat on the Husqvarna was like sitting on a plain, plastic seat pan. Even with a predominantly ‘standing up’ riding style, the seat would still make you sore after a day of riding.


So, the stock seat pan got treated with a Comfort 2.0 kit from Seat Concepts. The kit consists of new foam and a custom cover that allows you to choose your base and rib color. The comfort level of the seat is a night and day difference, but it’s still enough of a low-profile design so there’s no feeling of added bulk. It also provided just the right amount of grippiness (that’s a word now).

The Comfort 2.0 kit from Seat Concepts was a night and day difference from stock.


The bike was stripped of its original plastics and refitted with a complete Powerflow kit from Cycra. This kit was complete with a signature Cycra ‘Stadium’ front number plate, and the radiator shrouds come with added channels on the inside to direct air to surround the radiators.

The bike received the complete plastic treatment from Cycra with a new Powerflow kit, complete with Stadium front number plate.

Handguards are also a must have in off road riding, and the Cycra Rebound hand guards do a great job of combining the sturdiness of a metal frame with the freedom of independently mounted hand guards. Plus, they fold outward to prevent breaking or bending from falls.

Hand guards are a must have in off-road.

Pulling the look together was a set of custom graphics from Viscid Design Co. The matte look has recently taken the project bike scene by storm, and it came out even more awesome than imagined on this kit. The inspiration was to use just a handful of colors, including the Husqvarna blue and a splash of the yellow, to keep the look nice and clean. Viscid came up with the entire design on their own, and the combination of OEM cleanliness and factory flare gave the FX450 a uniquely awesome look.

Viscid Design delivered on the graphics with a clean, custom look.

A big thank you to all the great companies that got involved and helped with this build. It will see plenty of awesome trails and starting lines in the future!


For more information on the companies involved, check out their websites:



Pro Circuit

ProX Racing Parts

Seat Concepts

STI Tires


Pro Moto Billet


Viscid Design

Topics: featured, Powersports, BIKE FEATURES

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