Thanks to the use of plain bearings in the high-revving parts of the engine, the KTM 350SXF is capable of pumping out over 54
horsepower while having the rev limiter set at 13,400 rpm. That’s way up there. You don’t have to shift very often.
when steel drive plates hit against an aluminum basket.
As we all know, aluminum clutch baskets are notched by
the constant banging of the clutch plates against the soft
metal. It’s not uncommon for an aluminum basket to be
so badly notched that the clutch plates cannot move in
and out freely. Obviously, a steel clutch basket does not
notch. But, because the steel clutch plates are ratcheting
against a steel clutch basket, it is important that the two
steels have compatible hardnesses. Thus, for 2018, KTM
surface-hardens the clutch drive plates to promote a high
resistance to wear, scuffing and galling.
Q: HOW BIG IS THE CONTRIBUTION OF THE
A: On an electric-start motorcycle, the quickest
and easiest way to save weight is in the battery.
Switching from a standard-issue lead-acid battery to a lithium-iron-phosphate battery can save almost 3 pounds, and
that is exactly why KTM, Husqvarna, Honda and Yamaha
are using lithium-iron-phosphate batteries in 2018. The fly
in any battery’s ointment is cold weather. Batteries aren’t
as powerful at low temps as they are in warm weather.
The trick to using lithium-iron-phosphate batteries in cold
weather is to remember that this type of battery actually
increases its voltage as it gets warmer. How do you make
a battery warmer? You can make a lithium-iron-phosphate
battery warmer by hitting the starter button long enough
to kick the fuel pump on but not long enough to start the
engine. Do this three or four times and the battery’s voltage will rise enough to give the battery full starting power.
But, the best solution is to use a battery with more Cold
Cranking Amps (CCA). CCA is a rating used in the battery
industry to define a battery’s ability to start an engine in
cold temperatures. The CCA rating refers to the number of
amps a 12-volt battery can deliver at 0 degrees Fahrenheit
for 30 seconds while maintaining a voltage of at least 7. 2
volts. The higher the CCA rating, the greater the starting
power of the battery. For 2017 KTM has changed to a
much larger—although not significantly heavier—Sky Rich
HJTZ5S-FP battery that has more cold cranking amps. If
you have an older KTM with a Samsung C22S battery, you
should switch to the WPS replacement battery. It is as
strong as the bigger Sky Rich, but fits in the 2017-and-ear-
lier battery tray.
Q: HOW FAST IS THE 2018 KTM 350SXF?
A: Let’s not think of the KTM 350SXF as a mid-size
Open bike. It is really more of an oversized 250 than an
undersized 450. That said, this displacement suits a large
range of the riding and racing public. There are some
How to make it work. If you want the 54 horsepower that the 350SXF has to offer, you need to rev it to the
moon—and we mean rev it until the windshields of cars
parked in the pits crack. The key is to refuse to shift. Why?
The KTM 350SXF makes its max horsepower at its max
rpm. That means that if you don’t go to 13,400 rpm, you
will be leaving horsepower on the table.
How to make it work if you won’t rev it. If you
aren’t adept at revving your bike until the cows come
home, you will find that the 350 has a nice, mellow powerband in the midrange, albeit slower than its high-rpm output. If your brain won’t let you hold it wide open, you need
to do one of two things. First, buy a different bike, because
the 350SXF is only at its best in the nether regions of the
rpm band. Second, try gearing your 350SXF down by one
or two teeth on the rear sprocket. This perks up the low-to-mid power and makes the rev limiter more attainable.
How the 2018 works. Although KTM didn’t provide
any technical data when we asked about the 2018 map-