Live to Ride and Ride to live Free.

BMW 650 X-Challenge.

Based off the success of the F650GS and F650GS Dakar, BMW has revamped its dual-purpose machines with a trio
of 650 Singles that will simultaneously expand and eradicate the existing model range. The Dakar version will
have gone the way of the dodo after 2007 and the standard GS is likely to follow in the next couple years.
The popular six-fifty is still alive and well, however, inside the new X series, but as BMW aims to attract
new buyer demographics, the Xs have definitely taken a step away from their predecessors. We've already
reported on the most serious street machine of the three, the Xmoto, but well-funded off-roaders and
dual-sport riders will take a higher interest in the Xchallenge and Xcountry.

At the heart of this machine is a 652cc DOHC motor which is simply a re-worked version of the GS engine.
Utilizing a balancer shaft to negate the notorious 650 shiver, the 4-valve mill is good for a claimed 53
horsepower and 44 lb-ft of torque; that's three ponies more than the previous GS motor and with increased
response. The level of vibration rises to noticeable amounts as the revs climb into higher rpm, roughly 6000
revs, and are annoying by 8500. Regardless, the torquey motor is easy to keep under this rpm range if desired,
with the use of BMW's 5-speed tranny. Doing so requires moderately aggressive riding, but as we discovered,
it's the preferable method of transport with both machines, at least in the dirt.
In addition to the balancer shaft, other notable carryovers from the GS model are electric start, dual
ignition, electronic fuel injection, 5-speed transmission and a three-way catalytic converter.
Having the gas tank under the seat is a concerted effort to centralize mass in the X series. With 2.5 gallons
available, the X bikes have less than half the capacity of a KTM 640 and even less than the notoriously
limited Honda XR650R. However, an average of 54 mpg on the Xcountry means that you can concentrate on riding
more than stressing about your next fuel stop. BMW claims it's conceivable to expect nearly 62 mpg, but we're
plenty happy with mid-50s, especially considering that we weren't being shy about downshifting and revving the
piss out of each gear.

That means the
11.5:1 compression ratio of the oversquare powerplant is simple to get fired and runs smooth and clean no
matter what elevation or temperatures your adventure brings. A far-between, 6000-mile recommended maintenance
schedule is another welcome inheritance. The e-start is especially nice considering that the motor stalls
fairly easily for a 650 and absolutely refuses to bump start. A well-placed stab with your right thumb will
get things moving again. The left-side stainless muffler is new for the X models.
To help the motor rev faster, the airbox and exhaust were redesigned and the 280-watt alternator was trimmed
to reduce the amount of spinning mass. It's also tucked behind a magnesium cover for less weight. The whole
motor package is produced by Austrian company, Rotax, while the rest of the "German" machine is co-designed
and manufactured by Italy-based Aprilia.

The steel bridge, tubular frame utilizes the motor as a stressed member. Without a cradle, the side spars are
constructed of steel and pressed aluminum. The swingarm is a two-piece aluminum unit and the removable
subframe is also made of the lighter material. With 27.5 degrees of rake, 4.6 inches of trail and a 36.6-inch
seat height, these are the types of numbers you'd expect to see on a razor-sharp motocross chassis, but a
claimed dry weight of 318 lbs (344 wet) is more in line with our expectations for a 650 off-roader.


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