Motorcycle specifications KTM350 EXC-F 2017 The best part of the tests

The road to success is paved with obstacles. The test of mud, tears and sweat is the test of great champions and their immense qualities: a compact DOHC engine with an impressive power-to-weight ratio, impeccable handling and suspension on the most demanding terrain. And when you've reached your goal after countless adventures in an often unforgiving natural environment, you can measure the distance you've covered and let your joy explode. Antoine Meo, world enduro champion in the E2 category aboard his 350 EXC-F, knows all about it.

eNGINE

comparable in structure and dimensions to the 250 EXC-F engine, the new 350 EXC-F's powerplant is worthy of a 450. The fuel-injected engine has undergone a major facelift. More compact and lighter, it is nonetheless very powerful, and the greater torque is present throughout the rev range. Thanks to its new architecture and optimized shaft configuration, the engine has been shortened by 20 mm, a real plus in terms of mass centralization and driving pleasure. Another significant advantage of the new design is that the engine weighs just 28.5 kg, a reduction of 1.9 kg. The addition of an electric starter is also a real boon for riders. With a generous power curve across the entire operating range, the new 350 EXC-F is well equipped to satisfy professionals and amateurs at the top of their game. And since it's Euro IV approved, this orange KTM is also greener.

cULASSE

the centerpiece of the compact DOHC engine, the new avant-garde cylinder head features two overhead camshafts, rocker arms with 30% harder DLC-coated rocker arms designed to minimize friction, and a timing chain optimized to deliver impressive low-end torque. Four ultra-light titanium valves with new springs and bonnets and high-flow ports maximize flow for optimum operating range, and deliver breathtaking performance throughout the rev range up to 12,000 rpm. at this point, you've almost broken the sound barrier. Two new side brackets have been added to secure the engine to the frame and reduce vibration.

cYLINDER AND PISTON

the shortened, 88 mm-bore cylinder houses a proven bridge-box piston manufactured by CP. The geometry of the piston head, perfectly adapted to the new high-compression combustion chamber (12.3:1), features a rigid structure and reduced weight. The reduced oscillating masses give the engine its muscular, energetic character.

cRANKSHAFT

the crankshaft of the 350 EXC-F offers greater rigidity and uses a shorter connecting rod. More compact and lighter, the engine also gains in responsiveness. The crankshaft features a smooth connecting-rod bearing and two bearing shells press-fitted directly into the crankpin. This design is essential to support the very high rotational speeds of the 350 cm3 engine, ensuring unrivalled maximum power. This design extends engine life and crankshaft service intervals, saving time, effort and costs.

eNGINE MANAGEMENT SYSTEM

the Keihin engine management system with electronic fuel injection features an all-new 42 mm throttle valve body. Thanks to the injector's unique position, engine response is truly instantaneous. And for added convenience, there are independent adjustment systems for cold start and idle. Once the engine is sufficiently warm, simply lower the throttle to deactivate the cold-start mode.with an optional map selector, you can even increase the power curve and activate the traction control system for a little extra punch.

eLECTRIC STARTER

the 350 EXC-F comes with an electric starter as standard, a decisive advantage when the going gets tough. Operated at the touch of a button, Mitsuba's ultra-powerful starter is combined with a reliable lithium-ion battery and a lightweight drive system. Also with a view to lightening the bike, the kick starter has simply been eliminated.

bALANCING SHAFT

to balance mass forces, the engine uses a multi-function balancer shaft that simultaneously drives the water pump and the reworked timing chain.

gEARBOX

thanks to the low-friction coating of the selector fork, the 6-speed enduro gearbox is a model of precision and smoothness. The "zero dirt" design of the selector avoids clogging and jamming of the lever joint, and guarantees perfect gearbox reliability. All 4-stroke engines are equipped with a gear sensor that adapts the power curve according to the gear engaged and the terrain.

cRANKCASES AND ENGINE COVERS

the entirely new design of the molded crankcases offers a much more centralized shaft configuration. Engineers have succeeded in moving the crankshaft closer to the motorcycle's center of gravity, moving the clutch shaft back 11.1 mm and up 26.9 mm. This has shortened the engine by 2 cm, which is far from insignificant in terms of mass centralization. The new engine covers feature an advanced surface structure to prevent premature wear caused by the rider's boots.

cLUTCH

the 350 EXC-F 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 signature hydraulic clutch mechanism plays an essential role in the clutch's progressiveness and operation.

lIGHTING

the main objective of KTM engineers when developing the new EXC generation was to lighten the weight considerably. The result is clear: the current EXC models are among the lightest and slimmest enduro bikes on the market, despite the fact that they are equipped withthis is despite the fact that they are now equipped with a highly beneficial electric starter, whereas competing models still have to be kick-started. It's a sign that a strong current is flowing between the bike and its rider.

fRAME

the high-tech chromium-molybdenum steel frame is a model of lightness, flexibility and handling.the high-tech chromium-molybdenum steel frame, a model of lightness, flexibility and maneuverability, offers excellent stability and diabolical precision when cornering. Thanks to its high torsional stiffness and low longitudinal rigidity, this frame better absorbs the energy generated by the front and rear suspensions when jumping or negotiating 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. Mounted laterally, they help limit vibration levels. Two threaded inserts have been provided in the lower cradle tubes to add a shoe, should the need arise. 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 in deep ruts. To enhance ground clearance, the gear selector on EXC models has been raised by 6 mm compared to that on SX versions.

sQUIRRELING ARM

the new design optimizes the position of the PDS shock absorber for even smoother entry into action. In addition to an attractive weight saving (-220 g), cast aluminum offers ideal bending behavior. The one-piece molding process eliminates the imperfections inherent in welding, guaranteeing a more homogeneous, but also more meticulous, manufacturing quality.

fRONT SUSPENSION

another interesting new feature on this bike is the WP XPlor 48 inverted fork with separate damping circuits, developed by WP in close collaboration with KTM. Each fork leg is equipped with a spring and has a different function: the left leg handles compression damping, while the right leg handles rebound. To fine-tune each of these settings, simply turn the 30-notch knob above the plunger. To reduce the risk of bottoming, the fork features a longer, sealed hydraulic stop. High-quality materials, ultra-sophisticated production process, 300 mm travel, 200 g weight savings over the previous model : nothing has been left to chance to make the new XPlor 48 fork the ultimate in responsiveness and damping.available as an option, the new preload adjuster allows the triple compression spring to be adjusted without the need for tools. Operation is disconcertingly simple.

rEAR SUSPENSION

the bike is equipped with an all-new PDS XPlor shock absorber developed by WP. A true KTM trademark, the progressive damping system (PDS) has proved its worth time and again. As the shock absorber is connected directly to the upper part of the swingarm, it does away with the linkage system. This set-up has been redesigned with the new frame and swingarm architecture in mind. It's based on impeccable geometry and even more progressive damping. The body, also completely redesigned, features a smaller piston and a larger chamber. To save precious grams, the piston diameter has been reduced from 50 to 46 mm, the overall length has been cut by 2.5 mm and the shock absorber stroke has been reduced by 4 mm. As the shock absorber has been moved 5 mm closer to the central axis, the loads exerted on the swingarm and frame are virtually symmetrical. This also frees up space for the exhaust system. The second piston, combined with a cup-shaped limit stop (instead of a needle stop), is supported by a progressive-action spring. End-of-stroke heels are a thing of the past. This part has been lightened by over 600 grams. With its various machined and anodized components and its characteristic WP color scheme (black chamber, white spring and silver body), this ultra-sophisticated shock absorber makes a strong impression.

bRAKES

More responsive, more efficient and more powerful than ever, Brembo brakes will cope with any situation. These little jewels of technology are combined with Wave discs renowned for their lightness. The rear brake pedal has been lengthened by 10 mm, and the brake caliper piston is now smaller, for better brake proportioning. The stainless steel front brake hose features a protective sheath with a cable guide for the speedo wire. Optimum braking power is a must when you intend to push your machine.

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 an innovative throttle response mechanism, a sturdy aluminum handlebar and an ultra-simple guard adjustment system. 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. And thanks to two interchangeable cams, you can adapt the throttle response to suit your riding style. Engine maps selectable via the handlebar-mounted switch modulate the engine's power curve and enhance the bike's spirited character. To ensure efficient transfer of traction to the ground, the bike features a revolutionary traction control system, activated at the touch of a button.

fORK TIPS

the new generation features forged fork crowns with a 22 mm offset for improved fork retention and even more precise front-end behavior. The handlebars can be moved forward or back in four positions for a perfect grip.

aIR FILTER HOUSING

equipped with new intake snorkels, the air-filter housing has also been redesigned to provide even greater protection for the rider.the air filter housing has also been redesigned to better protect the air filter from clogging and ensure optimum air flow with complete peace of mind. The cage housing the new, extra-large Twin Air air filter is totally rigid, helping 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 you don't need any tools. And in a matter of seconds.

fUEL TANK

thanks to its transparent plastic, the ultra-light 8.5-liter polyethylene fuel tank lets you know at a glance how much fuel is left. To refuel, simply press the orange button in the center of the cap to open the bayonet mechanism. Four-stroke models feature an integrated fuel pump system and an additional fuel level sensor. The 90-degree fuel connection on new models enhances protection against damage.

eXHAUST

complying with the noise emission levels recommended by the FIM is a real challenge for all manufacturers. That's why KTM has spared no effort to develop a state-of-the-art exhaust system. All four-strokes feature new manifolds and a shorter silencer, mounted as close as possible to the engine. The benefits are threefold: more power, better mass centralization and enhanced driving pleasure. The internal design has also reached a significant degree of sophistication to keep noise levels well below FIM-recommended thresholds, while guaranteeing maximum rider sensations.

wHEELS

when it comes to wheels, KTM engineers know their stuff. Featuring ultra-light CNC-machined hubs and top-of-the-range Giant rims, these wheels guarantee maximum stability despite their limited weight. To top it all off, they're fitted with the latest generation of Maxxis tires. In addition to improved puncture resistance, the rear tire features a specially designed profile and internal structure to enhance grip in wet conditions. Whatever the terrain, these tires deliver maximum traction.

cOOLING SYSTEM

kTM's proven cooling system circulates coolant from the cylinder head through the frame triangle to the new aluminum WP radiators, equipped with a new cap system and made of a stiffer alloy. Its incredible efficiency is due to improved internal airflow management and advances in ventilation thanks to CFD (Computational Fluid Dynamics) calculations. Well thought-out radiator guards integrated into the front spoilers are particularly useful in the event of an impact.

sADDLE

tailored to provide a comfortable support surface for enduro riding, this ultra-strong saddle has been lowered by 10 mm to enable the rider to maintain perfect control of the bike, even on the most demanding terrain.

bATTERY AND WIRING HARNESS

as in the past, all EXC-F engines feature a proven electric starter - a KTM exclusive and a major advantage in motocross competition. The electric starter is combined with an ultra-compact lithium-ion battery claimed to weigh 495 g, 1 kg less than a conventional battery, despite being three times more powerful. And because it's so reliable, the kick starter is a thing of the past. The battery and wiring harness are now grouped together in a compartment above the air filter housing, to avoid interference with the electrical circuit when removing the rear frame.

bODYWORK

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. The result is convincing. Ergonomics and contact points for the rider have been carefully designed 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. Better still, they stay clean longer. The headlamp plate is also a model of ergonomics. And did you notice the trick used to prevent the brake hose from causing nasty scratches?

News and media credits: KTM