It shouldn’t surprise anyone to learn that these three
bikes share the same frame and chassis. Only the cradle of
the steel frame varies to accommodate the three different
motors. The suspension settings are identical on the 350
and 450, with only slight changes for the 250. All have the
same WP fork and shock, hooked up to the same
swingarm and the same wheels. They have the same
Brembo brakes, the same hydraulic clutches, the same
levers, even the same bodywork. Only the motors differ.
The four-strokes are five-speeds with electric start, and the
two-stroke is a five-speed with only a kickstarter.
KTM claims a slight weight difference between the 350
and 450, although on the incredible Dirt Bike scale, they
both tipped the beam at 240 pounds without fuel. The two-stroke, on the other hand, was an incredible 215 pounds
on the same scale.
On the dyno, the gap between the three is closer than
you might think. The 350 gained a surprising amount of
power for 2013, almost closing the gap on the 450. It has
a peak of 54 horsepower compared to 57 on the 450. But,
you have to wait longer. The 350 makes its best numbers
at 10,400 rpm, while the 450 does it at 9200. The 250
two-stroke makes 49 horsepower at 8500 rpm. So much
for the old-school conventions about two-strokes being
screamers and four-strokes being torquers. It hasn’t been
like that for years.
ON THE TRACK
It’s almost impossible to get off the 250 two-stroke
without a grin. To a man, every test rider said it was the
most fun to ride. The reasons are simple: it’s the lightest
and the slowest. That means you can twist the throttle
harder and feel like more of a hero. When a rider comes
out of a loose turn on the 250, he’s a frenzy of activity, with
exploding berms, fanning clutches, shifting gears and spinning wheels. It might be inefficient, but it’s great fun.
The 450 isn’t like that at all. It gets traction and blasts
forward with fearsome acceleration. To control the big
KTM’s massive output, the rider tends to shift very early
and try to find a mellow zone. At very low rpm, the 450
makes so much power that it’s almost impossible to get
below the meat of the powerband. The bike will rev, too, so
you can ride long sections of almost any track without
going near the shift lever. But revving the 450 isn’t especially pleasant. Aside from being hard to hang on to, it
vibrates and is quite a beast.
The 350 made such amazing strides this year that it now
runs just as fast as many 450s. The only difference is where
you keep the revs. On the 350, you tend to scream it happily.
It makes a lot of power in its own right, but it’s not as mean
and nasty at high revs as a 450. In fact, it’s quite comfortable
at high rpm. On the flip side, if you let the 350’s motor drop
too far, it doesn’t go anywhere. Eventually, it will climb back
into the happy zone, but it will cost you time.
Its’s hard to argue with power. The 450 is a brute.
The KTM250SX remains a bargin at $7099. It weighs 215
pounds, which makes it even better on a per-pound basis.
Where did all that power come from? The 350SX-F gained
6hp for 2013. Price: $8699.
KTM VS. KTM VS. KTM