2019 KTM 250 XC

Introduction

• KTM's Off-Road 250cc Two-Stroke Race Bike.
• Heavily updated for 2019.

Ahh, two-strokes. Most manufacturers have disregarded these classic machines and focused all of their attention to four-strokes. KTM; however, has continued development and offers a wide variety of two-strokes for all different applications. The folks down at 3 Brothers KTM (https://3brosktm.com/) helped us out with a 2019 250 XC and with a packed year of GP racing scheduled, we’ll be able to dissect this heavily updated bike inside and out over the next year. The 250 XC is KTM’s cross-country race bike based off of the 250 SX with some minor changes to accomodate off-road racing necessities. A 2.65 gallon fuel tank, 18 in. rear wheel, handguards and a kickstand, and some suspension/engine mods all make the XC a race ready off-road bike.

Changes

• Updated stiffer chassis for increased stability.
• New machined exhaust port and carburetor settings for improved engine performance.
• New pipe and silencer.
• Updated bodywork and ergonomics.

Alongside the four-strokes, KTM’s two-stroke XC line received a slew of changes for 2019. A 5mm longer rear axle slot on the swingarm, an updated stiffer chassis, and raising the engine by 1 degree around the swingarm pivot is all designed to improve stability. Similarly, aluminum head stays are now used for a claimed reduction in vibration while a 40mm extension of the subframe improves the stability of the rear fender. The orange brigade also reworked the airbox and the intake snorkels for improved airflow and a safer fixation of the air filter. The carb has new settings to match the airbox changes and is claimed to improve throttle response. The cylinder now features a machined exhaust port for improved performance.

A new exhaust pipe is claimed to be stronger and a little more tucked in to avoid contact with trailside debris while also offering more over-rev. The silencer now features aluminum mounts replacing the plastic mounts used for years while also including more durable packing for better noise reduction. The radiators are mounted 12mm lower for improved mass centralization while also slimming down the front of the bike and the waterpump has been reworked for 2019. Updated suspension settings outfit both ends of the bike while a stiffer upper triple clamp is claimed to improve stability. Finally, new bodywork including the fuel tank and a new seat make up the appearance for 2019 along with some BNG!

Power

• Smooth, strong, and linear power.
• Easy to ride.
• Lacks excitement at times.
• 6-speed transmission and E-Start is beneficial.

KTM first introduced the counterbalanced two-stroke engine to their lineup in 2017 and has continued to stick with it for good reason. The lack of vibration is welcomed with open arms by every test rider that’s swung a leg over the orange bike and makes long motos and races much easier to ride through. The power of the 250 XC mimics a four-stroke a bit in that it’s very smooth and linear. It’s also a bit deceiving as it doesn’t feel fast due to its lack of excitement; however, the bike is fast. Very fast. It has a smooth yet strong hit and continues to build up linearly through the mid to top. In years past, we’ve felt these bikes (mainly the moto bikes) signed off a bit early up top, but the 2019 XC pulls through and with the addition of the 6th gear, top speed is unparalleled by most other 250’s. Additionally the bike seems to find traction even when there is very little. From slick, hard pack conditions to wet and off-camber, the rear end hardly ever kicks loose under acceleration and drives through the terrain from the engine’s characteristics. The slightly heavier flywheel weight than what the SX model has aids this. Though minimal, the added weight is noticeable and it always feels like there’s a slight drag on the motor. In some instances it’s welcomed, but not always.

In reality, the bike has a strong motor that’s easy to ride and adjustable as well. It comes with two different power valve springs - aggressive and mild - along with the stock spring to change the characteristics of the motor. The stock (yellow) spring is a good, all around option that can be suitable to a variety of conditions, yet it wasn’t quite enough for our younger, more aggressive riders. After installing the aggressive (red) spring, it woke the bike up and felt almost like a new motorcycle. It livened up the engine and made it run more like a motocross bike than an off-road bike which is ideal for our application. The snappier power and improved throttle response fulfilled our wants. Additionally, the adjustable power valve is a nice touch for some more fine tuning to accommodate changing conditions and terrains. An odd shaped square tool (SEE HERE) is ideal for adjusting the power valve, but we’ve been using a flat blade screwdriver with no issues. We’re currently running it at 1.5 turns in from all the way out as a good base setting and adjusting it from there.

Stock jetting has also been a bit finicky in years past; however, we have yet to change it from stock. It is better but still not totally perfect. Due to personal preference, we turned the idle down to almost nothing (which helps boost the hit feeling), hit the tracks and trails, and haven’t looked back since! To note, we run 50/50 110 race gas and 91 with Maxima 927 at all times and haven’t experienced pump gas in this machine yet. So this may be why the stock jetting is still in the bike.

Additionally, the XC comes with a close-ratio, six-speed transmission which is ideal for almost any terrain. The gaps between gears are spaced evenly without too big or too small of a spread between any and the sixth gear comes in handy more often than we thought. At a few races already, we’ve hit 80mph and still climbing in stock trim. Impressive. The hydraulic clutch is liked by most and even our riders coming off a cable clutch adapted fairly quickly. And we almost expect the electric starting now. So common but it is one thing to point out since the XC’s blue competition does not have this feature.

Suspension

• Set up for East coast terrain in stock trim.
• AER 48 air fork works well and is easily tunable.

Off-road suspension is a bit tricky to setup in stock trim due to the widely varying terrains across the country. It’s nearly impossible to setup a bike that works well on the fast West coast terrain that also works in the tight and technical East coast terrain and the 250 XC showcases that. In stock trim, the bike is soft for GP style riding and racing for an expert with its focus seeming to be more East coast based. And with a good percentage of off-road specific bikes being on the East coast, that is the smart move. Many westerners seem to gravitate to manufacturers motocross models due to the somewhat similar terrain that Big6 and WORCS have-- more like motorcross. We messed around quite a bit with the AER 48 fork and coil spring shock but failed to get comfortable with the stock settings. Trail riding through the desert, the bike worked pretty good and was maybe even a tad stiff, but the bike proved to be too soft for moto tracks and GP terrain.

We felt the fork worked fairly good standard. KTM recommends a base of 9.4 bar, or 136 psi, in the fork, but the closest we got to comfortable on fast terrain was running 140psi in the fork with our compression at 10 clicks out and rebound at 15 clicks out. Overall, WP’s AER 48 air fork is a solid fork and quite easy to set up too. Check the air pressure in one chamber and bleed the air out of both forks like any other conventional spring fork and you’re good to go. It’s also very convenient when trying to setup the suspension initially as a quick change in air pressure is all that’s needed to adjust “spring rates” for varying terrain and speeds.

The shock was tougher to set up as it is stiff initially then tends to blow through the stroke. Running 105mm of sag, we tried stiffening up the compression but couldn’t find a happy medium between being too stiff initially and not having enough to take the hard hits. The rear end of the bike felt like a bucking bronco at times and never felt planted once we started pushing the pace in rough conditions. We feel with a stiffer spring rate and possibly some changes to the valving to make it more progressive, this can be remedied and we’ll be on our way to the races.  

Chassis - Handling

• Stable.
• Narrow, agile feel.
• Usual KTM/Euro ergonomics.

The 2019 KTM 250 XC received the same changes as the moto bikes for the new model year with an aim at increasing stability. We can comment that the ‘19 is very stable. The front end is planted and our confidence was never faltered at high speeds. Although a stabilizer is a common addition to an off-road race bike, it may not be completely necessary for the orange machine. Some of the increased stability may be due to the rear end squatting as it sits lower in the stroke, but we will continue to develop this and find out if the changes for 2019 keep working as we change the suspension.

The bike has a very narrow feel, though with the addition of the E-Start, it feels noticeably heavier than the SX and even some of the XC-F models. The bike is agile and easy to manage, but after riding it back to back with a new 350 XC-F, it doesn’t feel quite as light and nimble. Part of that may be due to the snapy yet  free revving motor of the 350cc four-stroke while the 250 XC has a bit of a heavy flywheel weight feel. Still the 250 XC turns pretty good and is easy to change directions in a hurry. Also, more often than not, correcting the bike when getting out of shape is quick and easy, here is where throwing a two-stroke around comes into play.

The ergo’s on this bike, or most European bikes for that matter, can be a little tough to get accustomed to, especially if coming from Yamahas. But with time, we felt pretty comfortable. Considering a lot of our testers run Fasst Company’s Flexx Handlebars, the handlebar isn’t our favorite. It’s a rigid bar and the bend feels a tad off as well being a little tall for our smaller riders. Additionally, the rider triangle leaves you sitting in the bike rather than on top of it with the bars coming into play here. As usual, the brakes work very good and stopping on a dime is a breeze with this bike.

We’ve encountered a few minor problems with this bike over the last 3 months of riding but nothing crazy. We’ve replaced our fair share of brake pedal return springs and have a Fasst Co. Spring Kit on order to solve this issue. Going to the older round spring can also fix this. Additionally, our petcock leaks fuel quite often when we turn the gas off. We’ve pulled it apart and cleaned everything out multiple times, but it always seems to come back at some point. Luckily, when we’ve left the petcock on reserve, we haven’t had any fuel leak out from the carb so it’s more of a nuisance when we want to remove the tank than anything.

Conclusion

• Easy to ride motorcycle.
• Engine tuning in stock trim is effective yet simple.
• It's a fast bike and stable at speed.
• E-Start and 6-speed transmission is much appreciated.

Overall, KTM’s 250 XC is a potent machine in 2019. In stock trim, the motor is capable of a lot and applicable to a wide variety of terrains and riding styles. The adjustments it offers in engine tuning specifically are really appealing. We’ve raced the bike quite a few times already in the few months we’ve had it and have been at the front of every start. The adjustable power valve and different springs can transform the engine character to suit just about every rider and terrain out there. Likewise, the bike is very stable at speed while also turning with the best of them. It’s fairly light and agile, though not the most agile bike out there, and combined with the motor, the bike is very easy to ride. Our only hiccup with this bike was the suspension, but that’s almost to be expected. For slower, East coast style terrain, the settings would be much more appreciated but West coast GP style terrain at higher speeds almost requires motocross settings making it tough to accommodate both.

As we spend more time with this bike, we’re going to gear up for a year of racing in the AMA Big6 Grand Prix Series racing the Pro 2 class. We’ll debut a build story on what we needed to make this bike ready to race for our needs. Yet as a stock platform with a wide duty list, we are very pleased. Stay tuned for more!