BMW Announces the New XChallenge
Photos and text courtesy
of BMW AG
The BMW G 650 Xchallenge is termed "the Hard Enduro
for the off-road enthusiast".
The BMW G 650 Xchallenge is a new departure for BMW
and has a lot to offer: This is an uncompromising
off-road machine with long spring travel and not one
single gram of extra weight.
In its design, the BMW G 650 Xchallenge is dominated
by proportions typical of a genuine Enduro a high-lying,
but smooth and flat fly line merging directly into the
high and slender rear end to offer the rider the ideal
seating position. Made of fracture-proof and
elastic plastic (mainly polypropylene), the fairing
components both light and robust are likewise ideal for
tough off-road requirements.
More: Complete and detailed
list of the
G650 X-Series specifications and model
The front wheel cover is fitted directly to the lower
fork bridge, giving the front wheel superior smoothness
and running freedom under all conditions. The slender
fairing, in turn, gracefully takes up the asymmetrically
contoured headlight featuring a reflector in free-form
design. Positioned off-center, the parking light,
finally, helps to provide that typical look of BMW
Motorrad further enhanced by paintwork in Aura White and
the Blue seat.
Benefiting from 270 millimeters or 10.63´´ spring travel
both front and rear, BMW Motorrad’s new Hard Enduro will
easily take on any challenge off the beaten track. Tube
diameter of 45 millimeters or 1.77´´, in turn, gives the
upside-down fork enormous overall stiffness, allowing a
The springs and dampers are all specially tuned for
off-road use, meeting the highest demands in every
respect. As a function of his own weight and personal
preferences, the truly ambitious Enduro rider is even
able to fine-tune the dampers on their inbound and
rebound strokes, the adjustment mechanisms offering
predetermined rest points for smooth, consistent
Again in the interest of minimum weight, the wheel
axle measuring 20 millimeters or 0.79´´ in diameter is
drilled hollow on both the front and rear wheel. The
rear wheel suspension also allows various adjustments
and set-ups, albeit of a very different character: Like
the BMW HP2 Enduro, the BMW G 650 Xchallenge features
the BMW Motorrad Air Damping System, a special
spring/damper system operating exclusively with air.
In its configuration and functions, the Air Damping
System is the same as on the HP2 Enduro and has merely
been adjusted in terms of weight and its running
The BMW Motorrad Air Damping System comes with a piston
inside, similar to the configuration in conventional
spring struts. Instead of hydraulic fluid, however, this
system forces out air through plate valves into a second
chamber, the damping effect being achieved by throttling
the flow of air.
Since gas is compressible, the air within the system
can act as a kind of spring replacing the usual steel
spring and thus offering the advantages already lauded
on the BMW HP 2 Enduro: Natural progression of spring
rates under high load (with growing pressure within the
Reliable and smooth operation minimizing the risk of
the suspension giving way (physical law of gases:
pressure increases as a function of temperature).
Natural progression of the damping effect under high
loads (the viscosity of air increases as a function of
temperature). Frequency-dependent, selective damping
effect. Resistant to overheating (no
temperature-induced weakening of the damping effect
under high loads). Simple option to adjust the
dampers to the load carried.
Low weight of the entire system and its components.
Individual adjustment and set-up of the suspension
matched to the rider’s weight and the load carried by
means of a water level presenting the normal position
and trim of the motorcycle.
The reduction in unsprung masses also improves spring
response and traction on the rear wheel. To the outside,
the spring strut is sealed hermetically and is therefore
protected from contamination, with any losses caused by
leakage being set off by filling in air through a valve.
The system adjusts very easily and conveniently to
different load conditions simply by varying the pressure
filling. And to pump up the system while traveling, the
rider has the option to use a hand-operated
high-pressure pump fitted beneath the seat of the G 650
A feature unique to this air spring damper system is
the choice of frequency related damping achieved by
varying the inner flow system together with the throttle
openings. And an important effect achieved in this way
is much better traction of the rear wheel on bumpy,
undulating surfaces: The damping effect can be
appropriately adjusted in the frequency ranges typically
encountered on the rear wheel swing arm as a result of
bumpy surfaces, the wheel thus following any such bumps
in an ideal motion, maintaining optimum ground contact
at all times.
The result is even better grip and traction when
accelerating all-out, as well as extra safety when
applying the brakes. Any risk of the springs sagging and
giving way, as is often the case on long, undulating
surfaces and under high loads, is largely excluded by
natural adjustment of the spring rates in the air
springs together with the frequency specific damping
effect: An adjustment bolt opening up a bypass in the
damper enables the rider to pre-set the damper
characteristics to two stages for either more
comfortable riding on regular roads or for a firmer
set-up on off-road terrain.
It almost goes without saying that the wheels and tyres
also meet the typical requirements of off-road riding.
Due to their better elasticity, spoke wheels come as
standard on the BMW G 650 Xchallenge, offering all the
features of lightweight technology. The wheel hubs made
of aluminium are hollow cast and are connected to the
epoxy-plated aluminium rims by extra-strong wire spokes.
To build up sufficient stabilizing gyro-forces also
on difficult and slow trails, the G 650 Xchallenge comes
with a front wheel measuring 21 inches in diameter and
running as standard on a 90/90-21 tyre, while at the
rear an 18-inch wheel running as standard on a 140/80-18
tire allows the use of specialized off-road tyres
Measuring a significant 300 millimeters or 11.81´´ in
diameter at the front and 240 millimeters or 9.45´´ in
diameter at the rear, the brake discs and indeed, the
entire brake system are conceived without compromises
for handling high loads. Apart from saving weight, the
cross-drilled Wave brake discs on the G 650 Xchallenge
have a better self-cleaning effect than conventional
And while the front wheel disc runs within a
double-piston floating caliper configuration, the rear
disc is held tight when required by a single piston
With its 15-tooth pinion and a 47-tooth sprocket, the
G 650 Xchallenge has a shorter final drive ratio than
the other two models in the new G 650 X model range.
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