MXA MOTOCROSS RACE TEST: 2018 KTM 250SXF
Q: FIRST AND FOREMOST, IS THE 2018 KTM 250SXF BETTER THAN THE 2017 250SXF?
A: Yes. Although the changes are small, the KTM 250SXF is better suspended, more durable, has improved starting and looks better.
Q: WHAT DID KTM CHANGE ON THE 250SXF FOR 2018?
A: KTM took the 2017 250SXF and refined it for 2018. In 2017 it was the lightest and fastest bike in the 250 class. Not only that, it had great suspension, Supercross-style pucker power, a hydraulic clutch, electric start, no-tools airbox, lock-on grips, an hour meter and multi-switch electronics. One year ago it was a bike that was ahead of its time. Guess what? It was so far ahead last year that it’s still ahead this year. Here are the updates to the 2018 KTM 250SXF.
(1) Forks. The WP AER air fork has been updated with a new air seal, air piston and rebound spring. On the damping side, there is a revised piston. The valving has also been updated.
(2) Shock. The WP shock has revised settings to match the updated fork settings.
(3) Frame color. KTM powdercoated its chromoly frames Factory Team Orange for 2018. They haven’t done this since 2015.
(4) Battery. A bigger, but not heavier, Sky Rich HJTZ5S-FP battery has replaced the previous Samsung C22S battery. The Sky Rich battery has more Cold Cranking Amps (CCA). This means that the battery no longer needs to be warmed up to get it to spin the engine over in cold weather.
(5) Clutch plates. The steel clutch plates now go through a process called “nitriding.” Nitriding is a heat-treatment process that diffuses nitrogen into the surface of the plates to create a case-hardened surface.
(6) Radiator guards. KTM radiator guards have been redesigned to lessen mud buildup, thus improving airflow in muddy conditions.
(7) C4 bearing. The transmission has gone from a C3 to a C4 bearing. The C4 bearing offers improved performance under high loads and high engine temperatures.
(8) Frame guards. Since the frame color changed from black to orange, the frame guards had to change also.
(9) MIM shift star. The shift star is now Metal Injection Molded (MIM) to provide better wear characteristics thanks to the close tolerances made possible by molding the shift star instead of machining it.
Q: WHAT TYPE OF RIDER DOES THE 250SXF ENGINE COMPLEMENT?
A: The KTM 250SXF strongly favors faster, more experienced riders because of its high-revving engine. Revving the engine to its max rpm of 14,000 rpm takes more guts than skill. The KTM’s incredible rev-ability is outside the comfort zone of older, slower and less experienced racers. It takes nerve to hear an engine scream at 14,000 rpm and not be tempted to shut it down. But, if you let off before 14 grand, you’re leaving power on the table.
Many people have a grudge against the KTM 250SXF based on past experiences. Prior to the 2016 models, the chassis, gearbox and suspension couldn’t handle the potent engine. It scared people off. The general dirt bike consumer, whether he knows it or not, wants comfort rather than power. When the 250SXF left a bad taste in riders’ mouths, they found comfort in the slower and more reliable Japanese models.
In response, and KTM is always quick to respond, KTM turned over a new leaf in 2016. The engine still screamed bloody murder, but usable bottom end and midrange were added. The chromoly chassis was forgiving, and even the often-panned WP 4CS forks worked adequately on the 250SXF in the hands of Novices and Vets. For slower riders who had the guts to get out of their comfort zone, the 2016 KTM 250SXF gave them a warm, fuzzy feeling when they hit the rev limiter while floating over chop. Nonetheless, all was not rosy for Intermediates and Pros. The 4CS suspension was way too soft—and a nightmare in the rough.
KTM responded again in 2017. The big game-changer was the addition of the 48mm WP AER air fork. For the first time in decades, KTM had a fork that worked well with riders from Beginners to Pros. It was the catalyst that made the KTM 250SXF come alive. The MXA wrecking crew still says that the 2017–2018 KTM 250SXF is best suited to faster riders, because it is omnipotent with a talented rider in the saddle. But, blessed with better suspension and acceptable low-to-mid power, the once all-pro 250SXF is now a valid machine for all skill levels.
Novices and Vets have grown to love this engine. There is one caveat. You don’t race a KTM 250SXF with the same skill set that you used on your YZ250F, KX250F, CRF250 or RM-Z250. It has to be ridden differently from what you are used to. If you don’t go for broke, bleed every gear dry and rev the bike until dogs howl in neighboring towns, it can feel like a slug. This is not a short-shift bike that you lug through the gears. This is a high-rpm, 43.79-horsepower powerhouse.
Q: WHAT IS THE BEST ATTRIBUTE OF THE 2018 KTM 250SXF?
A: Picking one out of the bunch is hard. A great attribute is something that every rider can gain an advantage from. A great attribute makes the rider better just by swinging a leg over the bike. A great attribute gives a rider confidence without him having to overstep his boundaries. But, if push comes to shove and we have to name the 2018 KTM 250SXF’s best attribute, we would say it’s front-end traction. That is not something you’ve heard discussed in most bike tests. It is often overlooked because it doesn’t show up as clearly on other brands. And, in truth, most people can feel the potent powerband more than a handling trait that is subtle.
The KTM 250SXF is a great-handling bike, but the way the front wheel tracks to the ground on the entrance of a corner is a momentous accomplishment. It doesn’t push (understeer). It doesn’t tuck the front (oversteer). It doesn’t hunt and peck. It doesn’t shake its head on corner exit. It’s rock solid. It tracks like it’s on rails. It does everything right. It is effortless to get the bike’s front end where you want it to go and, better yet, keep it on target from tip-in to exit. Trust us, all you have to do is point and shoot; you’ll score every time.
So why does front-end traction rank above the 250SXF’s flawless hydraulic clutch, class-leading WP AER air forks, awesome Brembo brakes and potent engine? Because it saves energy, builds confidence, minimizes mistakes, lessens the frequency of crashes, improves lap times and is something that no other bike can do better.
Q: WHAT IS THE 2018 KTM 250SXF’S WORST CHARACTER FLAW?
A: Yes, it does have a flaw, but luckily this one can be fixed for about $25. In 2017 the KTM engineers dropped the 2016 250SXF’s 13/50 gearing combo for an ultra-tall 14/51 sprocket set. We didn’t like it immediately and asked KTM’s in-house American test riders who selected this gearing. They said it came from the European test riders. The Euros felt that the potent engine could pull the tall gearing. And it can, with a faster rider at the controls, but it isn’t sparkling out of corners, doesn’t pull as hard up hills, and keeps Novices and Vets stuck in second gear when they should be in third. If you have a 2017 or 2018 KTM 250SXF, you should consider changing back to the 2016 bike’s 13-tooth countershaft sprocket.
We do admit that the WP shock handles better with the 14-tooth countershaft on the bike. We attribute this to a reduction in chain torque with the straighter drive line; however, to get the gearing we want and still keep the 14-tooth countershaft sprocket would require a 53-tooth rear sprocket, which would feed more chain torque back into the system. It should be noted that the Factory Troy Lee Designs KTM race team runs a 14/53 gearing combo.
Q: IS THE 2018 KTM 250SXF WORTH THE EXTRA MONEY?
A: It is no secret that KTMs and their stepbrothers at Husqvarna are expensive. The 2018 KTM 250SXF can claim to be $100 cheaper than the Husky FC250 at $8699, but it is a lot more expensive than an RM-Z250, CRF250, KX250F or YZ250F. You will be paying at least $800 to $1000 more for an orange bike. So, why spend the extra coin?
We want to give you the knowledge to make the best decision for your means, age, size and skill level. We admit that paying this premium in years past was a hard pill to swallow. Why? Because you would easily spend another $1000 to get 4CS suspension that worked. On the flip side of the coin, the extra KTM premium did deliver electric starting, a hydraulic clutch, super brakes and a powerful engine. To put the dollars into perspective, an electric starter and hydraulic clutch on a Japanese 250 would cost around $1000.
Now, with the 2018 KTM 250SXF, it is a whole new ball game. The 2018 is the lightest 250 four-stroke made. It has the best brakes, highest rpm, best handling, hydraulic clutch and the first air fork that not only works well but is easy to live with. Do you want an electric-start YZ250F? Forget about it. How about a 43.79-horsepower RM-Z250? Put $5000 in an unmarked envelope and drop it on Jamie Ellis’ doorstep. Looking for a 218-pound Honda CRF250? All you need is $7000 worth of titanium.An aftermarket pipe for a Japanese bike can run $900—and , in absolute truth, the KTM 250SXF doesn’t need an aftermarket pipe.
The extra $1000 for the KTM buys performance that is unmatched. If you don’t need any of those extras, you should be able to find leftover Japanese 250s at discount prices at your local dealer.
Q: WHAT DO WE THINK ABOUT THE WP SUSPENSION COMPONENTS?
A: The 250SXF has a balanced chassis matched with a WP shock that is in harmony with the WP AER forks. This makes setting up the WP components easy. Just set the sag at 105mm and start running the fork at the recommended 156 psi to be in the ballpark. The 2018 KTM 250SXF has great straight-line stability, corners superbly, holds up in the stroke on big hits and floats over chop.
The addition of the AER air fork made the 250SXF a complete race bike. WP’s innovative air-fork design makes it simple to adjust and easy to find an air pressure that works for you. The stock 156 psi is great for fast Intermediate to Pro-level riders. Every MXA test rider went out on compression no matter where the psi was set. This allowed the stroke of the fork to flow through the bumps, making them more supple. We have test riders who run a psi as low as 130 psi, but we suggest that Vets and Novices run in the 140 psi to 145 psi range; fast Novices to Intermediates should run around 150 psi.
The WP AER air forks are a step ahead of the WP shock. They normally dance in harmony, but the shock can get out of rhythm at times. In whoops and square-edged bumps at speed, the WP shock can catch you off guard with the rear end stepping out. Riders were more timid in whoops than on a YZ250F. The YZ250F handles these conditions with more stability and less movement.
Q: WHAT SETTING DO WE USE ON THE MULTI-SWITCH?
A: We think the multi-switch and its maps are still in the infancy of their development. For right now, on most bikes, the maps are more of a marketing tool to sell customers on the versatility of the machine. Yes, the maps work, and yes, they do change the power; however, the usefulness of this is blown way out of proportion. How so? There is only one map on the 2018 KTM 250SXF that any MXA test rider used. It was Map 2, the aggressive map. The stock map (Map 1) has a mild bottom to mid, which makes the bike harder to ride, not easier. The Traction Control (TC) setting helped in muddy conditions by robbing bottom and mid power.
Since no one in his right mind would choose to run Map 1 or Traction Control except in extreme conditions, we’d like Map 2 to become the stock map (Map 1). And, instead of having a map that suffocates the lower half of the rpm range, we’d like the new Map 2 to enhance the low-to-mid power by trading some of the top end for a powerband that is easier to ride for less skilled riders. That way, the KTM would have all the bases covered— fast on top, fast on the bottom and traction control.
As for Launch Control, on a 250 four-stroke, it seems a little silly, but it is still viable on concrete and muddy starts.
Q: WHAT DID WE HATE?
A: The hate list:
(1) Gas cap. It sticks, but it isn’t as bad as trying to get the YZ250F’s gas cap off.
(2) Exhaust. You have to remove the shock to get the pipe off. Like jigsaw puzzles? This will be fixed in on the 2019 models.
(3) Sprocket bolts. We don’t have as much of a problem as we used to, but they still come loose.
(4) Gearing. The ultra-tall 14/51 gearing is not right. The 14-tooth countershaft has minor benefits, but those go out the window when it’s matched with a 51-tooth rear sprocket. Either change the 14-tooth countershaft to a 13 or use a 53-tooth rear sprocket with the standard 14 front as the race team does.
(5) Spokes. Always check the spoke next to the rear rim lock. If it is loose—and five times out of 10 it will be—tighten all the spokes. The spokes are an issue, and if you are fast, heavy or race on jump-filled tracks, consider aftermarket wheels, or at the very least stronger spokes.
(6) Neutral. We love how well the KTM shifts from gear to gear, but we hate how hard it is to get into neutral when standing still. KTM does this purposely to eliminate false neutrals.
(7) Shock collar. You can’t win with the stock plastic shock collar. Sometimes it works and sometimes it doesn’t. KTM warns against hitting it with a hammer and punch, as it will damage the notches. The only way to turn the shock collar without hitting it is to pry on the notches in the collar with a long screwdriver while turning the spring by hand—although most times you need to use the frame for leverage.
(8) Torx bolts. Don’t buy a KTM without buying a full set of Torx tools. You won’t be able to work on your bike if you don’t. KTM used to supply a tool pouch filled with an assortment of Torx sizes with every bike, but it doesn’t anymore.
(9) Maps. We like the aggressive map. Now we want a map with more bottom and mid, not less.
Q: WHAT DID WE LIKE?
A: The like list:
(1) Handling. You shoot and it scores.
(2) Hydraulic clutch. This clutch is durable enough to last in the hands of a clutch abuser. We know, because the MXA wrecking crew has several test riders who use the clutch as an auxiliary throttle.
(3) Weight. KTMs keep getting lighter while Japanese brands keep getting heavier. At 218 pounds, the 250SXF is the lightest bike in its class. It is 10 pounds lighter than a 2018 Honda CRF250.
(4) Power. The KTM 250SXF is the horsepower king. It revs to the moon. We love the numbers, but we would like a more usable powerband for mere mortals.
(5) Hour meter. The best thing about the showroom-stock KTM hour meter is that they put it on for you.
(6) Air filter. It is painless to change.
(7) AER forks. These forks are awesome. They work great for Beginners and Pros.
(8) Grips. We love the ODI lock-on grips, but if your have tender hands consider switching to glue-on grips (they have ticker rubber). We wish the ODI’s weren’t mounted with a #15 Torx.
(9) Tires. The 250SXF is shod with our favorite Dunlop MX3S tires front and rear. Beware! The front tire will shred side knobs if ridden on hard-packed dirt.
(10) Brakes. The best in the business by a mile.
Q: WHAT DO WE REALLY THINK?
A: If you are a serious racer, this is the bike to buy. It will cost you more, but we promise that you will save money in the end.
MXA’S 2018 KTM 250SXF SETUP SPECS
WP AER FORK SETTINGS
It’s important to note that any recommended air-fork setting is totally dependent on the weight and speed of the rider. MXA can’t choose a middle-of-the-road air pressures that will work for a wide variety of skill levels. The trick to getting the most from your WP AER air forks is to find the proper air pressure for your weight, speed and track. We’ve gone as low as 130 pounds, but we typically start testing at the OEM-recommended air pressure and then lower it in 2-psi increments until the forks don’t feel like they are dropping into their stroke. Typically, AER forks ride high in their stroke with the stock pressure. Once we find the right pressure, wqhich we determine by getting almost full travel during a lap of the track, we focus on clicker changes. For hardcore racing, we recommend this fork setup on the 2018 KTM 250SXF (stock specs are in parentheses):
Spring rate: 130 psi (Novice),140 psi (Vet), 150 psi (Intermediate) 154 psi (Pro)
Compression: 20 clicks out (12 clicks out)
Rebound: 15 clicks out (12 clicks out)
Fork-leg height: Third line
Notes: Except for extreme temperature changes, you should not have to change the AER’s air pressure; however, we do bleed the outer chamber constantly, which is accessed via a 10mm hex head or #20 Torx. Even if you own a #20 Torx, don’t use it on the air-side leg, because the bleed screw strips out easily.
WP SHOCK SETTINGS
With heavier riders, the shock rides low in the stroke. We turned the high-speed compression in a turn from stock to keep the rear end from dropping. For hardcore racing, we recommend this shock setup for the 2017 KTM 250SXF (stock specs are in parentheses):
Spring rate: 42 N/m
Race sag: 105mm
Hi-compression: 1 turn out (2 turns out)
Lo-compression: 13 clicks out (15 clicks out)
Rebound: 14 clicks out (15 clicks out)
Notes: As a rule of thumb, we use the high-speed compression to iron out the balance of the rear suspension, typically varying by a quarter-turn in either direction.
Had you subscribed to MXA, you would have read this complete bike test when in came out back in November. Click the box below to subscribe.