KTM 250 EXC-F 2018:A recipe for success
Fill an agile, state-of-the-art chassis with an engine delivering class-leading power and torque. Then dress it with top class components, ensuring that the new 4-stroke maintains its edge over the competition. The result is a READY TO RACE dual sport suitable for amateur explorers, while still satisfying the pros. Eat that, adversaries.
KTM R&D, KISKA Design and the factory racers had their say
in shaping the plastics with one goal: complete harmony
between rider and bike. Perfect ergonomics and contact
points provide maximum comfort in movement on the EXC-F.
The I-beam structures of the front and rear fenders guarantee
maximum stability and a low weight thanks to well thought-out
construction and mounting. They also stay cleaner for longer.
Clever brake hose routing on the front number plate
prevents wear and tear.
New graphics convey the READY TO RACE character of
the 2018 KTM EXC-F model line.
The light and compact KTM 250 EXC-F engine delivers class-leading
torque and power over the entire rev range. The architecture
with an optimized shaft configuration makes for excellent mass
centralization and effortless rideability, at only 27.6kg. And that’s
including the comfort of an E-starter. The power curve reaches for the
sky over the entire length of the rev range, begging for another
gear at 12,800rpm. This makes the new KTM 250 EXC-F brilliantly
suited to both amateur riders as to pros at the peak of their ability.
And it’s Euro IV homologated, so the planet will love you for it.
The centerpiece of the compact DOHC engine is this cutting-edge
cylinder head. It features light, dual overhead camshafts with
friction-optimized cam followers boasting a hard DLC coating.
Four lightweight titanium valves and high-flow ports maximize the
flow rate for an optimal power band and outstanding performance
across the seemingly endless rev range of 12,800rpm. Two
lateral stays allow an efficient fixation of the engine to
the frame and reduce vibration.
The KTM 250 EXC-F’s crankshaft utilizes a short connecting rod,
making for an overall compact and lightweight engine with a
snappy power delivery. A plain big (bottom) end bearing with two
force-fitted bearing shells runs directly on the crank pin. This
design is a must for the extremely high engine speeds and the
unrivaled power of this 250cc engine while also enhancing the engine’s
durability for long crankshaft service intervals
The KTM 250 EXC-F is fitted with a unique E-starter as standard,
which is a clear advantage when it comes to crunch
time in the heat of battle. A strong starter motor made
by Mitsuba will fire time and time again at the push of a button.
Even under extreme conditions, thanks to its more heat resistant O-ring.
The engine is fitted with a precise 6-speed Enduro transmission,
with solid shift engagement thanks to a special low-friction coating
on the shift forks. An advanced ´No Dirt´ gear shift lever design
prevents mud or dirt build-up in the joint for trouble-free rides.
All KTM 4-stroke engines are fitted with a gear position sensor
that syncs the power curve to each gear. In MY18, the transmission
shaft gets a new C4 bearing that has a bigger overlap in the case.
This means reliability even under extremely hard conditions.
Think GP-level riding. In knee-deep sand.
Crankcases and engine covers
The design of the die-cast engine crankcases allows for a centralized
shaft configuration, moving the crankshaft close to the bike’s
center of gravity. All hail mass-centralization! The engine covers feature
an advanced surface structure to reduce the wear caused by
the rider’s boots.
To balance the mass forces, the engine uses a multifunctional
balancer shaft that also drives the water pump and timing chain.
Engine management system
The state-of-the-art Keihin engine management system with
electronic fuel injection features a 42mm throttle body. Thanks
to its unique injector position, the engine’s response gives
a whole new meaning to the word ‘instantaneous’. Separate
circuits for cold-starting and idle make on-site adjustments
easy. Push the throttle back when the engine is warmed
up and the cold start mode disengages.
The KTM 250 EXC-F employs the KTM-developed DDS clutch
(damped diaphragm steel) with a wear-free steel basket
and extremely heat resistant clutch plates and new, nitrated
steel liners. This clever design employs a diaphragm spring
instead of the usual coil springs, making for considerably easier
clutch action. A diaphragm spring also leaves sufficient space for a
damping system to be integrated into the clutch hub. The goal
is traction, but durability is as well. Light operation and
telepathic amounts of control are standard with this
hydraulic Brembo actuated clutch.
The high-tech, lightweight chrome-moly steel frame has a knack for
easy handling, outlandish rideability, precise cornering and
excellent stability. You can also count on high torsional
rigidity and low longitudinal stiffness. This results in better
absorption of the energy created from the front and rear
suspension sucking up jumps and bumps. In short: more
comfort and less rider fatigue. Laterally attached, lightweight
engine head stays (the connection between cylinder head and frame)
contribute to a reduced vibration level. Two threaded inserts
in the lower cradle tubes allow for safe fixation of an
optional skid plate. The engineers could pull off all that, while
making their frame a big fat kilogram lighter than that of the
lightest competitor on the market. In addition, it is easier to maintain,
easier to work on and supplies more space for the tank
and other components. The bike also features an extra-light
subframe made of stable aluminum profiles, which tiptoes
the scales at less than 900g.
Sophisticated ´No Dirt´ footpegs prevent jamming up of the pegs,
even when digging in deep ruts. The pegs on the EXC models
are 6mm higher than the ones used on SX models, which benefits
ground clearance. But you can swap them at will.
This state-of-the-art swingarm allows for an optimized mounting
position of the PDS shock absorber, providing more
progressive action. Furthermore, the cast aluminum design
guarantees lower weight and a perfect flex behavior. The single-component
casting process also eliminates any inconsistencies and weak points.
The WP Xplor 48 upside-down fork is a split fork developed by
WP in close collaboration with KTM. It is fitted with a spring
on both sides but features separated functions for each fork
leg: compression damping is fitted on the left side, while rebound
is on the right. The forks can easily be adjusted for compression and
rebound with the twist of a dial on the top of the forks. New
outer fork tubes and a reworked setting make for more sensitivity,
improved damping behavior and a reduced weight. In addition,
a sealed hydro-stop guarantees excellent resistance to bottoming-out.
Due to high-quality materials and a state-of-the-art production
process, the new WP Xplor 48 fork – with approx. 300mm of travel – has
outstanding response and damping characteristics. A comfortable preload
adjuster can be retrofitted and allows for a simple spring preload
setting in three steps without tools (standard, +3mm, +6mm).
The PDS is kind of a KTM trademark where the shock absorber is
directly connected to the upper side of the swingarm. This
setup boasts the best possible mounting geometry and
provides amazingly progressive damping. The shock absorber is
mounted close to the centerline, which means nearly
symmetrical loads for the swingarm and frame and more space
for the exhaust system. A second piston works together
with a closed cup (instead of a needle) towards the end of the stroke
and is supported by a progressive shock spring for exceptional
bottoming resistance. Various machined and anodized
components and a distinctive WP color trim make this a valuable,
high-end product compared to the less refined shock
absorbers of the competition.
You can’t brake any harder, better, faster or stronger. High-tech
Brembo calipers are combined with lightweight Wave
brake discs. The steel-flex front brake hose has efficient protection
and there’s an integrated channel for the speedometer cable.
First you outrun them, then you outbrake them.
KTM engineers know how to handle handlebars. This tapered unit,
made of high-strength aluminum by NEKEN, features a throttle
assembly with a robust aluminum body and easy free-play
adjustment. An ODI volcanized grip sits on the right, while
on the left side of the bar a comfortable ODI lock-on grip
requires no glue or wire to secure it. You can retrofit two interchangeable
throttle cams, for different response characteristics to suit your
specific needs. With an optional map select switch you can select
an alternative power characteristic and activate the unique
traction control, a major benefit under wet riding conditions.
The EXC-Fs are fitted with forged triple clamps with an
offset of 22mm, ensuring a solid grip of the fork and
precise handling. The handlebar is adjustable forwards
and backwards over 4 positions, so the EXC-F will fit
you like your favorite gloves.
Air filter box
The air filter box design offers maximum protection of the air
filter against soiling, while ensuring maximum airflow in a
quiet way. The large Twin Air filter is mounted in a stiff cage,
which at the same time holds the system in place. This
design is so simple; you can pop a fresh one in with
a face full of mud – without tools and in seconds.
The lightweight polyethylene tank has a capacity of 8.5 liters.
You will always be able to see how much fuel remains at
a glance, thanks to the see-through plastic. By pushing the orange
release button in the center of the fuel tank cap, the bayonet
mechanism makes refueling quick and easy. It is fitted with an
integrated fuel pump system and a fuel level sensor. Additionally,
the fuel line features a 90° connector to the tank for better
protection against damage.
Noise limits are a real challenge for every manufacturer. Therefore,
KTM has put a lot of effort into the development of its
exhaust systems. All 4-strokes are fitted with a short high-end
aluminum muffler, mounted as close to the engine as possible.
This means more power, extra mass centralization and better rideability.
An advanced internal design reduces the noise sufficiently to sit
safely below the noise limit, while still providing the engine response
and performance that is expected from a KTM.
The EXC-F’s wheels feature lightweight, CNC machined hubs
and high-end Giant rims guaranteeing maximum stability at
minimum weight. The wheels are fitted with MAXXIS tires – perfect
for surefooted performance off-road and stability on-road.
Battery & Wiring harness
A strong lithium ion battery breathes life into the engine
and contributes to low vehicle weight. The lightweight battery
and wiring harness are centralized in a compartment above
the air filter box, allowing the mechanic to remove the subframe
without getting in conflict with the electronics.
A happy mechanic is a good mechanic.
KTM’s proven cooling system routes the coolant from the cylinder
head through the frame triangle, directly to aluminum
radiators made by WP. Thanks to flow optimized internal circulation
and CFD-calculated ventilation, the system is superbly efficient.
In addition, new radiator protections improve heat dissipation.
Especially in the mud. They are also integrated into
the front part of the shrouds to protect the radiators in a crash.
|Design||1-cylinder 4-stroke engine|
|Clutch||Wet, DDS multi-disc clutch, Brembo hydraulics|
|Ignition system||Keihin EMS|
|Frame design||Chrome-molybdenum steel central-tube frame|
|Rear suspension||WP Xplor PDS shock absorber|
|Suspension travel front||300 mm|
|Suspension travel rear||310 mm|
|Front - Rear Brake system||Disc brakes|
|Brake discs - diameter Front||260 mm|
|Brake discs - diameter Rear||220 mm|
|Steering head angle||63.5°|
|Wheel base||1482±10 mm|
|Ground clearance (unloaded)||355 mm|
|Seat height (unloaded)||960 mm|
|Total fuel tank capacity approx.||8.5 l|
|Weight without fuel approx.||103 kg|