MXA RACE TEST: THE REAL TEST OF THE 2024 KTM 250SXF

Q: FIRST AND FOREMOST, IS THE 2024 KTM 250SXF BETTER THAN THE 2023 MODEL?

A: KTM made minor changes to the suspension and updated the graphics. Otherwise, it’s the same bike as last year.

 Q: WHAT’S NEW ON THE 2024 WP XACT SUSPENSION?

A: WP reworked its air forks and shock for the 2024 models with the goal of increasing comfort and adjustability at both ends. Both the shock and fork valving are different from that of the 2023 production KTM 250SXF, but the changes are so small that you might not notice the difference if we didn’t tell you. 

Forks. The compression shim stack has some minor changes to make the mid-valve damping feel more fluid and comfortable. KTM did not touch the rebound side of the fork’s damping, nor are there any alterations to the suggested air pressure or clicker settings; however, WP is hoping the end user will be more willing to make adjustments with the clickers now.

Shock. The shock has new high-speed compression damping settings with a smaller gap per adjustment. The goal was to get the high-speed compression dial to make smaller adjustments per dial movement. WP made incremental changes to reduce the damping effect per click by 50 percent. With last year’s setup, WP thought it was easy to go too far with each adjustment. What did they change? The 2023 WP shock had 15 high-speed compression shims, while the 2024 shock has 23 shims. The increase in the shim stack made each adjustment smaller and offered the rider twice as many options.

Q: HOW DOES THE 2024 KTM 250SXF RUN ON THE DYNO?

A: KTM’s 250SXF engine has long been known for its high-revving capabilities. It has consistently been faster than the rest of the 250 four-stroke powerplants, but it has lacked excitement, thrust, snap, pop, girth, pep—whatever you want to call it. By the seat of your pants, it doesn’t feel as fast as it really is. When KTM introduced the all-new engine on the 2022-1/2 KTM 250SXF Factory Edition, with an even bigger bore and shorter stroke, we expected it to blow our socks off on corner exits. Unfortunately, it didn’t do that. It was stronger, but you still have to rev high into the rpm range to get the best bang for each gear’s buck.

Compared to the Honda, Kawasaki, Suzuki and Yamaha, the KTM 250SXF engine scores higher numbers on the dyno at 7000, 8000, 9000, 12,000 and 13,000 rpm. It is only beat out by the Kawasaki at 10,000 and 11,000 rpm. Surprisingly, the KTM 250SXF engine is as much as 2 to 3 horsepower ahead of the Yamaha YZ250F at every point on the dyno curve; however, there are many riders who still think the YZ250F is faster, and they prefer it over the 250SXF. Crazy, right? 

There’s no doubt that the Star Racing Yamaha has consistently had the fastest 250 four-stroke on the track for the last few years. Of course, comparing factory teams’ bikes to the OEM version of their bike usually doesn’t make for a valid argument, but in this case, many of our engine-building friends (like Jamie Ellis of Twisted Development) have boasted about their ability to make exceptionally strong engines with the Yamaha YZ250F platform. The ClubMX Yamaha team is a privateer effort with very little help from Yamaha, and their Twisted-built engines run competitively with all the factory 250s. 

Q: HOW DOES THE 2023 KTM 250SXF RUN ON THE TRACK?

A: The changes made to this engine for 2023 (and the 2022-1/2 Factory Edition) were focused on creating more mid-range thrust. In the end, the 250SXF is better than before, but not by leaps and bounds. With a long time to develop the new ’23 engine (the previous engine had been around since 2016), we expected a more noticeable improvement. Still, it’s understandably difficult to make drastic mid-range improvements when you already have the fastest engine in the class. 

The Honda CRF250 and Yamaha YZ250F engines are more exciting in the low-to-mid rpm ranges, and you don’t have to hold each gear as long to reach the engine’s full potential. To ride the KTM 250SXF to its full capability, you can’t be scared to wring its neck out for all it’s got. The 250SXF does its best work at 13,000 rpm, which takes some guts to reach. Great KTM 250SXF racers aren’t scared to hit the rev limiter and ride super high in the rpm range. If you aren’t comfortable revving the 250SXF, you’ll be leaving power on the table. Also, make sure to install the ventilated air box cover as well. More air into the engine livens up the power. 

As for mapping, KTM wanted a bigger difference between its maps when they introduced this bike last year, and they achieved it. All our test riders stay in the green map full-time, because nobody wants to detune a 250. The white map is only good for featherweight riders and novices who want to mellow out their 250SXF. As for the TC (traction control) button, we stay away from it like the plague on the 250SXF. It sounds so bad, you’ll think your ECU is having issues. In the TC map, the power is detuned so much that the engine can’t get out of its own way.

Q: HOW DOES THE 2024 250SXF HANDLE ON THE TRACK?

A: The new-generation 2023–2024 KTM chassis is 6 pounds heavier than before (224 pounds now compared to 218 in 2022), and the rear end rides taller now than it ever has. The chromoly steel frame, updated swingarm, aluminum/carbon composite subframe and new WP rear shock that were added onto this bike for 2023 have significantly changed the way it handles.

It’s very stable and balanced—much more so than the previous package. Our biggest complaint is that it has a taller seat height—taller in the pits and on the track. However, once you get a few laps on it, you become accustomed to the taller ride height. It’s no secret that MXA test riders prefer the Husqvarna FC250 for its lower seat height when it comes to cornering, especially on dry and slick tracks where finding traction is of the utmost importance. On rougher, deeper and jumpy tracks that demand more hold-up from the suspension, the test riders preferred the extra travel of the KTM 250SXF suspension. We might squawk at the taller seat height, but the 2024 KTM 250SXF is one of the best-handling bikes in the class. It’s almost fool- and idiot-proof.

Q: HOW IS THE SUSPENSION?

A: For our intermediate and pro testers weighing around 175 pounds, the 42 N/mm shock spring is too soft, but it was great for our slower and lighter testers. Despite internet complaints, most MXA test riders like the performance of the WP XACT air forks; however, they do require more effort from the riders than coil-spring forks—far more. You have to set your air pressure before you ride and bleed the air screws in the morning. Then, if your bike is sitting in the sun, your air pressure will go up. As you ride, your air pressure will go up as well. 

We set the shock sag at 105mm with the forks on the second line and start with the stock clicker positions and air pressure settings with all our testers. WP’s stock settings meet the needs of a wide range of riders. Plus, thanks to the air forks, the MXA wrecking crew can change the spring rate of the forks for lighter-weight or heavier riders in minutes. Try that with coil-spring forks.

While Honda, Kawasaki and Suzuki have spec’d Supercross-stiff forks on their 250 four-strokes, KTMs (as well as Husqvarna and GasGas) come with forks that work for little Johnny who just got off a 125 two-stroke and only weighs 135 pounds. And, they work for little Johnny’s dad, who hits the scales at 225 pounds on a good day. With the WP fork pump, changing the air pressure (aka fork spring) is easy. 

We love the adjustable-by-hand compression and rebound clickers. They make the testing and tuning process much easier; however, the rebound clicker on the shock is on the clevis, and it is very hard to get to. We still use a flathead screwdriver for that.

Every MXA test rider likes the fact that the WP air forks are over 3 pounds lighter than coil-spring forks. The 3 pounds that far forward and high up on the chassis can be felt. MXA test riders always mention it when switching from air forks to spring forks. 

Q: WHY DOESN’T WP DITCH THE AIR FORKS FOR SPRINGS?

A: For the first time since 2017, KTM spec’ed WP coil-spring forks on their cross-country bikes for 2024. After a seven-year run of air forks on its off-road bikes, WP finally caved. Of course, the motocross models still use the WP XACT air forks, but KTM has constantly debated going back to springs. Over the last seven years, aftermarket suspension tuners have been able to rake in money by making drop-in spring conversion kits for WP air forks. Shockingly, WP even jumped on this bandwagon by creating its own 6500 kit. (We tested a version of it; see page 77). 

What are the benefits of coil springs? The best part is that you don’t have to worry about your air pressure going up or down. Of course, there are still bleed screws on coil-spring forks that build up pressure, but that’s minuscule compared to air-fork-pressure buildup. It makes good sense for the off-road bikes to come with coil-spring forks because they’re ridden for longer periods of time, and you don’t want to worry about an air fork pumping up. Plus, off-roaders experience harsher chatter bumps, rocks and roots out on the trail, and need softer, plusher and more compliant forks, while motocross guys need forks that can handle big jumps, consecutive whoops and higher speed. 

What are the benefits of air? With air forks, the bike is 3 pounds lighter—so much lighter that the front end can actually be placed wherever you want it. Add in the fact that you can change the “spring rate” in 60 seconds, and you get great bottoming resistance and a plush but linear fork feel (as long as the pressure is set correctly). Even the factory Red Bull KTM factory riders have switched from their factory WP Cone Valve spring forks to re-valved WP XACT air forks during this year’s outdoor and SMX races. 

The spring-versus-air debate will never end, but one thing is certain—the WP XACT air fork is the best production air fork ever made, and in many back-to-back tests, it is competitive with the spring forks on Hondas, Yamahas and Kawasakis. Yamaha’s Kayaba SSS fork is on the top of the heap.

Q: WHAT DID WE HATE?

A: The hate list.

(1) Spokes. Check your spokes after every moto when breaking in your wheels. They will come loose and take some time to set. If you don’t catch them early, it turns into a bigger problem.

(2) Traction control. Traction control detunes the 250SXF far too much to be taken seriously. 

(3) Radiator cap. The new plastic minicycle-style radiator cap was added because Marvin Musquin kicked his radiator cap off on the track once. Ironically, the factory Red Bull KTM team doesn’t even use it. They went back to the standard cap. 

(4) Bodywork. The rear fender must be removed to get the side number panels off, and the fork guards hit the front fender if they aren’t aligned properly.

(5) Weight. The 250SXF used to be the lightest bike in the class. Last year, it gained 6 pounds. Not good. 

(6) Slide-N-Guide. Keep an eye on the chain buffer pad. We recommend TM Designworks.

(7) Price. No matter how much technology is added to the bike, 10 grand is too much.

(8) Seat height. The KTM got taller; we prefer the Husqvarna’s lower profile.

(9) Brake-pedal tip. The foot pad on the rear brake pedal can be crushed in a close encounter of the dirt kind.

(10) Buttons. The buttons that activate start, stop and other electronic aids are hard to use because of their low profile (and the fact that we always try to activate them with a gloved hand).

Q: WHAT DID WE LIKE?

A: The like list.

(1) Quick Shift. Although most of our testers don’t like using the “QS” mode on the track, it’s nice to have the option to turn it on or off whenever we feel like it. 

(2) Shock collar. The shock collar was new for 2023, and we love it! It is much more durable than the 2022 and prior models. 

(3) Engine. We wish it had more low-rpm excitement, but it’s still the fastest in its class. 

(4) Air forks. The WP XACT air forks work great if you take the time to learn how to adjust them. 

(5) E-start. The electric starter on the Austrian brands is second to none. It rarely hesitates like the Japanese brands.

(6) Crossover. We appreciate that you can buy a KTM 250SX two-stroke or any other KTM, Husqvarna or GasGas bike and almost all the parts (except bodywork between brands), will cross over. 

(7) Brakes. The Brembo brakes are top of the line. How do we know? Kawasaki broke ranks with Nissin to add a Brembo front caliper, master cylinder and levers on the 2024 KX450. Japanese brands don’t use European parts unless they are better.

(8) Clutch. The Austrians have the best clutch, hands down, which is why Yamaha and Kawasaki copied it.

Q: WHAT DID WE REALLY THINK?

A: At $10,199, the 2024 KTM 250SXF is the second-most expensive bike in the class (only $100 less than the Husqvarna), but you get what you pay for. The 250SXF is a true race bike. It has the fastest engine, topnotch suspension (that can easily be tailored for your size and speed), the most durable clutch and the strongest brakes. Of course, it’s not perfect, but it is MXA’s reigning 250 shootout winner for good reason.