Motorcycle specifications KTM250 SX 2017 Sniper

In the world of motocross, the new KTM 250 SX boasts one of the best power-to-weight ratios in its class. Confident in its strength, it's ready to take on even the most complex 4-stroke bikes. With the punch needed to excel on all types of track and terrain, and an uncommon sense of placement thanks to its ultra-light chassis, the darling of KTM's R&D teams and motorsports specialists is destined to become the future king of the discipline.

eNGINE

the 250 SX's 2-stroke engine has long had the reputation of being the most powerful in its class. All the hopes placed in this segment have paid off, confirming the enormous potential of KTM's 2-stroke engines. Inexpensive, these engines shine for their simplicity. And what about their power-to-weight ratio? It's simply mind-boggling. To put its convictions into practice, KTM has completely redesigned the engine structure of the 250 SX and made a number of improvements: new shaft assembly for improved mass centralization, new exhaust-controlled cylinder with dual TVC exhaust valve, new balancer shaft to reduce vibration, 5-speed gearbox and hydraulic DDS clutch. Lightning-quick, this compact engine has everything to dazzle performance-seeking racers and seduce budget-conscious riders.

cYLINDER

the 250 SX's 66.4 mm-bore cylinder features all-new ports and a completely redesigned exhaust control. A sophisticated mechanism for the exhaust channels on the side support ensures smooth power delivery. What's more, the engine's character can be altered in a matter of seconds by adjusting the two dedicated exhaust control springs. Whatever the track conditions, you're sure to find the most appropriate settings. Nothing has been left to chance: the new water jackets inside the cylinder and cylinder head dissipate heat more effectively. The ultra-light cylinder-head side brackets have been reworked to give greater rigidity to the engine-frame assembly.

eNGINE HOUSING

to improve mass centralization, engineers chose to raise the clutch shaft and crankshaft by 8 and 27 mm respectively inside the all-new molded crankcases, resulting in exceptional handling. This clever design also frees up space for the installation of a balancer shaft, so that the miles can be swallowed up at full speed and in complete relaxation. Another interesting innovation to keep the engine as radiant as in the early days: new engine covers with an elaborate surface structure designed to reduce wear caused by the rider's boots.

bALANCER SHAFT

numb hands and feet are not inevitable. The engine's new design has made it possible to use a side-mounted balancer shaft, which contributes to a considerable reduction in vibration levels (50% less at the handlebars and footrests). This obviously has a beneficial effect on driving pleasure.

cARBURATEUR

starting with AM 2017, all KTM 2-stroke models will be equipped with the new MIKUNI TMX carburetor instead of the usual Keihin carburetor. This 38-mm flat-barrel carburetor offers a clear improvement in power delivery over the entire operating range. It is also less sensitive to changes in altitude and temperature.

vILEBREQUIN

a model of reliability, the engine has been carefully balanced to minimize vibrations. Thanks to the replacement of the cylinder, piston and cylinder head, displacement is now 144 cm3. As the crankshaft remains the same, the engineers killed two birds with one stone.

cLUTCH

the 250 SX uses a DDS (Damped Diaphragm Steel) clutch developed by KTM, featuring a wear-free steel clutch housing and heat-resistant clutch plates. A special feature of this design is the use of a diaphragm spring instead of the usual coil springs, giving the clutch greater flexibility. The diaphragm spring also leaves ample room for a damping system integrated into the clutch hub, to enhance traction and durability. The clutch bell is lighter, the clutch nut has been reworked, and the pressure plate helps optimize oil supply and cooling. Brembo's hydraulic clutch mechanism plays an essential role in the clutch's progressiveness and operation.

gEARBOX

although this new 5-speed gearbox provides the same gear ratios as its predecessor, the engineers have focused on making gear shifting even smoother and more precise. As safety is also an essential parameter, the selector adopts a new "zero dirt" design that prevents the lever joint from jamming due to dirt. Because even greasy terrain enthusiasts take a dim view of mud when it gets lodged in the wrong places.

eXHAUST

the combustion chamber has been carefully designed to deliver even more power and torque. This engine is a marvel of explosiveness and solidity.

fRAME

the high-tech chromium-molybdenum steel frame is a model of lightness, flexibility and maneuverability, offering excellent stability and diabolical precision when cornering. Thanks to its high torsional stiffness and low longitudinal rigidity, this frame absorbs the energy generated by the front and rear suspensions when jumping or going over a bump. The ride is more comfortable and less tiring. The dropouts that link the cylinder head to the frame are as light as ever. Side-mounted, they also help to limit vibration levels and refine the bike's trajectory in bends. The engineers can be proud of their work, as the frame is now one kilo lighter than the lightest competing frame on the market today. Every effort has also been made to facilitate maintenance and free up space for the fuel tank and other components. The ultra-light rear section, made of stable aluminum profiles, weighs in at less than 900 grams.

fOOTREST

sophisticated "zero-dirt" footrests prevent the gear selector from getting dirty, even when riding in deep ruts.

aIR FILTER HOUSING

the air filter housing protects the air filter from clogging and ensures optimum air flow. The cage housing the extra-large Twin Air air filter is totally rigid, making it easier to hold the system in place. The design is so simple that you could replace the filter even with your face covered in mud. And without the need for any tools. And in a matter of seconds.

oSCILLANT ARM

as well as saving weight, cast aluminium is ideal for bending. The one-piece casting process eliminates the imperfections inherent in welding, guaranteeing not only more homogeneous, but also more meticulous manufacturing quality.

fUEL TANK

the ultra-light polyethylene fuel tank has a capacity of 7 liters. The internally threaded fuel cap ensures easy, reliable closure.

hANDLEBARS

when it comes to handlebars, KTM engineers have always known which way to go. This NEKEN handlebar, with its high-strength aluminum profile, is no exception. It features rubber silent-blocks and can be adjusted to two positions. starting with AM 2017, the handlebar is secured by two clamps (lower part) and a new trigger guard (upper part) that improves torsional rigidity. It's also easier to replace the handlebars should they become bent after a nasty fall. right: an ODI vulcanized handle; left: the ODI lock-on handle, as comfortable as it is practical, thanks to its glueless, wire-free mounting system.

sADDLE

tailored to provide a comfortable support surface, this saddle is as durable as it is comfortable. For added pampering, riders will benefit from a new saddle cover on the AM 2017, designed to enhance grip and feel.

cOOLING SYSTEM

kTM's proven integrated cooling system circulates coolant from the cylinder head via the frame triangle to aluminum radiators supplied by WP. Its incredible efficiency is due to improved management of internal airflow and advances in ventilation thanks to CFD (Computational Fluid Dynamics) calculations. The well-thought-out radiator guards integrated into the front spoilers are particularly useful in the event of an impact. For KTM, every detail counts.

wHEELS

featuring ultra-light CNC-machined hubs and top-of-the-range Excel rims, the wheels guarantee maximum stability despite limited unsprung weight. They are fitted with the latest-generation Dunlop Geomax MX 3S tires.

fORK

another interesting new feature on this bike is the WP AER 48 inverted fork with air spring and separate damping circuits, developed by WP in close collaboration with KTM. The damping functions are on the right, the air spring on the left. The left fork leg features a double-chamber air cartridge system to prevent any loss of pressure. Should the outer seal leak, the pressure exerted inside the inner cartridge will hold the bike in position. The air spring is easily adjusted to the rider's weight using a single valve. No special tools are required: the standard pump will do the trick. The right-hand fork leg incorporates a cartridge specially designed to adapt to the type of damping required. Simply turn the 30-notch knob to the desired position (compression up and rebound down) to select the appropriate setting according to track conditions and rider preference. For AM 2017, it's also important to point out that the outer tubes of the AER 48 fork have been redesigned to optimize bending characteristics, provide more flexibility and limit friction forces. They have also lost 265 g, which is far from insignificant. More comfortable and sensitive than ever, these forks are ready to be put through their paces.

fORK TIPS

high-quality CNC-machined fork crowns have been a KTM trademark for years. Enabling precise steering, they significantly enhance the flexibility characteristics and, thus, the action of the fork. For AM 2017, the design of the upper fork crown has been revised to accommodate the new plungers. The handlebars, fitted with rubber silent-blocks, are secured by two clamps (lower part) and a new trigger guard (upper part) that improves torsional rigidity. Handlebar replacement is also easier, for example in the event of a fall. An hour meter on the upper fork crown indicates when it's time for maintenance or refuelling.

dAMPER

the WP shock absorber was developed with the new frame and swingarm architecture in mind, as were the linkage system and the WP AER 48 front fork. With its various machined and black-anodized components, this ultra-sophisticated shock absorber makes a strong impression compared to less well finished competing products. It features a new setting and a softer spring to match the new front-end setting.

bRAKES

more responsive, more efficient and more powerful than ever, Brembo brakes are ready to face any situation. These little jewels of technology are combined with Galfer Wave discs, renowned for their lightness. For AM 2017, the rear brake pedal has been lengthened by 10 mm and the new brake pads are now less aggressive.

cARENAGE

kTM factory riders collaborated on the bike's design with KTM R&D specialists and the Kiska design agency, with a single watchword: to create perfect harmony between rider and machine. Particular attention has been paid to ergonomics and rider contact points for maximum freedom of movement. The lowered saddle offers superior comfort, especially at the rear. The special shape of the front and rear mudguards is a perfect example of intelligent design: thanks to a well-thought-out structure and assembly, these mudguards guarantee maximum stability, while being lighter at the same time. Best of all, they stay clean longer.

Information and images credits: KTM