Powermonger: The 2015 KTM 250SXF produces the most
horsepower in the class. It’s also the most difficult to ride.
Thank heavens: After years of benign neglect, the 250SXF
finally comes with decent forks. We like the WP 4CS forks.
( 6) Wheels. Gone are the silver Excel rims; in their
place are black-anodized Excel rims with black spokes
and silver aluminum nipples. KTM also shaved 50 grams
off the rear sprocket. Dunlop Geomax MX52 tires come
( 7) Clutch. New O-rings are used on the oil-pump
suction screen for increased durability. The clutch basket
has been revised for improved durability and weight
savings, while the clutch springs are designed to be
more consistent under stress over time.
( 8) Additional updates. The KTM 250SXF comes
standard with Renthal 827-bend Fatbars, but the new
Domino grips feature a softer dual-compound design.
Additionally, the bike is outfitted with new in-mold
Q: WHAT CHANGES WERE WE HOPING
THAT KTM WOULD MAKE TO THE 2015 KTM
A: Here are the two key areas holding the 2015
KTM 250SXF back from world domination:
(1) Engine. We hoped that KTM would finally
address the elephant in the room. For many years the
MXA wrecking crew has begged KTM to produce a 250
four-stroke powerband that appeals to their American
audience. That didn’t happen. KTM’s target consumer
is an Expert-level racer. This strategy is wrong for two
reasons. (a) The cream of the motocross crop already
spends thousands of dollars on engine work to make
their stock bikes as fast as possible. KTM’s 250SXF is
fast out of the crate, but it won’t remain in stock trim in
the hands of a Pro. (b) Although motocross celebrates
those fearless individuals who set the fastest lap time
at their local track, the vast majority of riders are at the
Novice- and Vet-level speed. They don’t want a high-rpm
missile that requires you to rev it to 14,000 rpm and
never shut off. The 2015 KTM 250SXF powerband is too
tough to keep on the pipe for those who live from 8000
to 11000 rpm. There is a reason why Americans love
the KX250F and YZ250F powerbands—it’s because they
aren’t anything like the KTM 250SXF powerband.
( 2) Gearing. The MXA wrecking crew has hated
the gearing on the 250SXF for years—and for years we
have tried to salve our wounds by gearing it down. We
would swap the stock 50-tooth rear sprocket for a 51 (for
most tracks) or a 52 (for tight, Supercross-style circuits).
Our goal was to lower the ratios to try and make the
high-rpm KTM hit sooner and pull harder in the middle.
It worked, but it didn’t make the 250SXF any easier to
For 2015, we decided to run a completely new round
of gearing tests. After trying 49-, 50-, 51- and 52-tooth
rear sprockets, we elected to run the 13/49 combination.
This taller gearing gives us a 3. 77 ratio, which is
considerably taller than our previously preferred 13/51
gearing’s 3. 92 ratio. But we were stuck between a rock
and a hard place with the 250SXF gearing, because by
going taller instead of lower, we traded shifting to third
sooner for staying in second longer. As a result, the
powerband was broader, engine braking reduced, shifting eased and the suspension less loaded.
We would be remiss if we didn’t say that not every
MXA test rider was happy with this gearing diversion—
Vet and Novice test riders still preferred to run the 13/51
2015 KTM 250SXF