Release The Ruckus
Think "unbridled 2-stroke performance" and you'll probably see a KTM 250 SX in your mind's eye. For good reason too - there isn't much to compare it to. The KTM 250 SX takes that even further with a slew of fresh chassis enhancements, making it even more of a legend and one deserving of the record books.
Easy Suspension Adjustment
As always, the suspension boasts an easy tool-free setup at both ends, ensuring you chase down the podium in total control. On the rear, a hand-adjustable dual compression option allows riders to adjust high- and low-speed settings in a matter of seconds. The forks on the front end are also easily modified thanks to hand-adjustable clickers on the bottom of the fork shoe and top cap.
Electronic Fuel Injection
Pre-mix gets a remix across the 2-stroke KTM SX range, with Electronic Fuel Injection setting the standard. Now there's no more fiddly jetting setup pre-race. And thanks to the Keihin EFI and reed valve case design, you can be guaranteed of laying down optimal power at any altitude, all of the time. For 2026 there is a new fuel protector cap: you'll still have quick and easy access for maintenance but now more safety against any outside damage and accidental opening as well as preventing dirt from entering the sides of the connector.
Electric Start
Picture this; You're 7 laps into an absolute ripper of a race. You miss your line and end up stalling in a deep rut. But don't sweat it. All you do is press the starter button and you blast off again to take the flag. This is the reality on the KTM SX models. Thanks to a 12,8V 2 Ah lithium ion battery placed under the rider's seat, a high-quality starter and pickup and super robust design, the only thing you'll be kicking - is ass.
Serviceability
The KTM SX and SX-F range is engineered and designed to provide riders with easy-to-access service parts, as well as suspension adjustability. This permits faster trackside and off-season maintenance, as well as simplifying motocross for novice riders without pit crews. For 2026, a new threaded radiator cap allows easier and faster opening with reduced force.
EFI + Power Valve
With EFI comes great rideability. Along with the electronic fuel injection and a power valve on the KTM SX models, allowing for more usable power throughout the rev range. Smoother power means better traction. Better traction means holeshot heaven!
Performance
The KTM 250 SX has always represented the very best of unsurpassed power and lightweight construction. The simplicity and low maintenance cost of the 2-stroke motor have made it a favorite amongst motocross riders for generations. The KTM 250 SX enters the race paddock with an overall engine weight of only 23,9 kg, setting the motor as the benchmark in the highly competitive 250 cc class.
Selectable Maps
The KTM SX models features a map select switch allowing the racer to switch between 2 engine maps. Map 1 provides a linear, predictable power delivery, while Map 2 gives it the full beans with crisp, explosive power output.
Absolute Control
Get ready for a full-on berm assault. The KTM SX and SX-F machines received major frame updates directly from KTM Factory Racing efforts. For starters, the area around the rear shock mount is streamlined, with engine mounts and cut-outs for improved chassis flex. The front area of the frame has an optimum wall thickness with renewed engine mounts.
Ergonomics
Tank shrouds using bi-compound plastics channel air towards the radiators more efficiently, while a concise fuel tank roll, makes for a tighter, more secure fitment, reducing the chance of frame scrubbing and dramatically improving durability. All this works alongside the specially-developed rider triangle, to provide unmatched knee contact and gripping surfaces - especially when standing on the pegs.
WP XACT Fork
Let's get the technical parts out of the way first; the 48 mm WP XACT AER forks fitted to the KTM SX and SX-F line-up features a capsulated air spring and pressurized oil chamber for progressive and consistent damping, while oil and air bypasses reduce pressure peaks. In combination with the mid-valve damping system, all this provides exceptional feedback and rider comfort. The fork also has settings which not only compliment the frame and rear linkage, but ensures stellar performance at all levels. Speaking of settings, these are easily adjusted via a single air pressure pre-load valve, as well as easy-access click adjusters for compression and rebound. Additionally, the WP air pump needed to adjust the fork's air pressure is provided as standard in the buy-pack.
WP XACT Shock
Keeping things in check at the rear, the WP XACT rear shock for uses settings directly from the KTM Factory Racing Teams. The frame and shock geometry mean more ground clearance at the linkage, making it less susceptible to bottoming out. Small diameter linkage bolts save weight, while new linkage seals refine rear shock response and advanced damping characteristics.
Stability
An upgraded rear brake pedal finds its way onto the 2025 KTM Motocross range, adding additional stiffness, bending resistance and braking feel to the overall package. At the other end, a forged steering head connection and CNC-milled triple clamps, make for the perfect alignment of the fork tubes. This precise geometry of the fork clamps ensures highly responsive and smooth fork action – not to mention unwavering stability when charging across ruts and onto the podium.
Tires
Getting power hooked into the dirt is a tough job. However, hours of research and testing have led the 2025 KTM Motocross range to the Dunlop GEOMAX MX34. Providing unmatched stability and control at the highest level, these rubber hoops feature a new carcass and rubber compound that improves damping and absorption, maintaining performance up to 30% longer. New Progressive Cornering Block Technology also improves grip in the berms, while a new rear pattern with 11% taller and 44% wider center block for increased traction and control everywhere else. Lastly, this unique block arrangement works to dispel mud buildup, ensuring traction in even the muddiest of track conditions.
Consistency
Count on a durable chain guide and chain guard and minimize the chances of hooking on external objects - especially in extremely muddy terrain while reducing dirt build-up around the swingarm and rear sprocket. For 2026 we've also modified the fixing points and routing of the wiring harness so it's less prone to wear and damage.
Energy absorption
Besides the expertly crafted, hydro-formed, laser-cut, and robot-welded frame being engineered to provide exceptional rider feedback and straight-line stability, it consists of specifically calculated parameters of longitudinal and torsional flex. This means the frame acts as a "shock absorber" of sorts, making for a less harsh ride, resulting in less rider fatigue over many hard laps.
Ground Clearance
No one enjoys a bad hook-up. Good thing, then that the shock absorber geometry on the 2025 KTM 250 SX improves ground clearance of the linkage, with the topology-optimized die-cast footpegs being less susceptible to hooking on deep ruts, and take-offs when scrubbing.
