The KX250 Experience
When I bought my first KX250, I was often asked if I had any regrets
about switching from a purpose-built woods bike to a motocross bike
for woods racing. The answer was relatively simple, actually: my 2002
KTM 300MXC started gathering dust next to the KX. But it is a valid
question – what did I like better, and why? As with most of the
important issues in life, there is no simple answer. There is no right or
wrong. They were both good, but often in different ways. As much as
you may wish me to provide a definitive solution to the conundrum of
which to buy, Japanese motocross bike or European woods bike, I
cannot, because I am not you. What I can offer is my opinions on how
my KX and my KTM performed under various conditions and rider
styles. After reading these thoughts, you may still have questions.
You may still have uncertainty. But such is life, young grasshopper.

General Overview- KTM
I’m in my um-teenth year of KTM ownership, and had I not attempted
the KX woods conversion I would have been satisfied with orange for
a good long time. The 300 motor is suitable for just about any skill
level and no matter how experienced the rider, most can adapt their
riding style to the low-end grunt that this engine is known for. There’s
no unfriendly hit in the powerband, just smooth power from bottom to
top. With its low-end muscle, climbing up a steep, technical hill can
be accomplished with less use of clutch than your average 2-stroke
bike. Bigger-bore 4-strokes may be the kings of smooth power
delivery, but the KTM 300 is the thumper’s closest oil-burning rival.

Since the first two KTM’s I owned were purpose-built woods racers,
they came pretty well set up for hare scrambles and enduros.
Suspension on both bikes was excellent, with the exception of the
43mm forks on my ’02 (a do-it-yourself-revalve helped a lot). Both
KTM’s came with lighting coils and even though the MXC didn't have
an odometer like the EXC, its front wheel could drive a mechanical
odometer by simply attaching an OEM odometer drive (which of
course doesn't matter anymore, because mechanical odometers are
mostly history). Fuel capacity was just over 3 gallons, which was long
enough to run a 2+ hour hare scramble without stopping for fuel. O-
ring chains and 18-inch rear wheels were stock, as were kickstands.
All of these things made riding in the woods just a little more
enjoyable.

General Overview- KX250
Since it was engineered for motocross, the KX was far from race-
ready in the woods. However, I must diverge from our topic here and
mention that no bike – not a single one – is race-ready out of the
crate. Forget what the magazines say about KTM’s. I’d never race one
without a skid plate, hardened wheel spacers, rear rotor guard, heavy
duty inner tubes, metal handguards, and of course a steering
damper. So no matter what bike you get, if you plan on racing it in the
woods, you're going to do some stuff to make it suitable for woods
riding.

Now back to our topic. Motocross engineering involves specially tuned
engines that are made for sprinting, basically, and the suspension is
tuned for hard landings. Think of it as the difference between running
the 200-meter hurdles and the 5,000-meter steeplechase. The guys
who run those races might look similar in that they generally have two
arms, two legs and usually some cool shoes, but inside they’re tuned
differently. Woods riders need an engine with smoother power for
tight, twisty trails and suspension that soaks up smaller, choppy
bumps.  In stock form the KX250 (or any other motocross bike) was by
no means smooth in the woods. But what it lacked in trail-friendliness
could be bought in the aftermarket. I started with the suspension by
sending it to W.E.R. Racing for a revalve. Softer springs, front and
rear, also helped make the ride comfortably plush. I then added an 11-
oz flywheel weight to smooth out the engine. The toughest part about
riding a stock KX250 in the woods was that it wanted – demanded,
actually – nearly constant throttle. Before he switched to an RM250, I
used to give Missouri fast guy Zach Bryant some good-natured
ribbing about never letting the throttle on his RM125 slip under the
halfway point (ever), but that's the way MX bikes must be ridden in
order to go fast. Unfortunately, it’s hard to be smooth when the bike is
screaming at 8,000 RPM’s in a tight, first-gear section of trail filled with
loose, baseball-sized rocks. The extra inertia contributed by a flywheel
weight keeps the engine RPM’s from quickly dropping off to next-to-
nothing when you let off the throttle. It also gives more lugging power
at lower RPM’s.

Other necessities for the KX250 were a 3.1-gallon IMS tank and an
RK X-ring chain to replace the non-O-ring chain. Its 19-inch rear
wheel aside, in this state the KX was moderately equivalent in hare
scramble readiness to a KTM out of the crate (the KX would still lack
some
enduro-readiness, however).

The KX in the woods was not entirely comparable to my KTM,
however. It was a different beast. While the KX probably generated
similar horsepower as the 300’s, it delivered that power in a distinctive
way. Since it was bred as a motocrosser, the KX liked to be ridden
aggressively. It shined when I was on the gas with the rear wheel
spinning. The KX loved to turn, which made it cut through tight, curvy
trails with ease. Stopping power was excellent, with a strong front
brake that halted the bike quickly. At speed, the KX was remarkably
stable.

What my KTMs Did That the KX Did Not
If I’m nearing the end of a long, tough enduro, there’s no bike I’d
rather have than a KTM 300. Late in the race, when my energy level
was running on empty and the race organizers saved the roughest,
most technical trails for last, the 300 let me lazy. The KX, on the other
hand, did not reward lethargic riders. If I was fatigued, the KX tired me
more. Also, some purpose-built off-road bikes have wide-ratio
transmissions, meaning a higher top speed for those rare occasions
when you need to drag race through a wide-open trail. My 1999 KTM
300EXC and 2003 Gas Gas 300EC had these transmissions, and I
liked them lots. The KTM's have been using hydraulic clutches for
many years, which I feel are superior to cable clutches in terms of
operation. The action is smooth and always feels the same, no matter
how much you heat up the clutch.

What the KX Did That my KTMs Did Not
At a race pace, the KX generally felt more confidence-inspiring,
starting with the front brake. Where my first two KTMs often left me
wondering if I’d get stopped in time, the KX could be late-braked
without fear of overshooting a turn, thanks to a very strong, firm front
brake. It also felt more stable at higher speeds. Both KTM’s were
prone to headshake when the throttle was opened up in 5th gear, but
not the KX. The engine had a substantial hit in its powerband, which
was useful on bermed grass tracks. Throw the KX into a berm with a
healthy dose of throttle, dump the clutch and hang on. I was also a
little more satisfied with the linkage rear suspension in terms of
tracking, versus the PDS linkage-less shock on the KTMs.

The Conclusion
So which was better? Again, there’s no definitive answer, but here’s
what I think:

  • The KTM 300 was a great bike for all abilities, but probably more
    so for beginners and intermediate skill levels. The engine was
    extremely forgiving and the low-end grunt meant less clutch work
    and less wheel spin. It was also simpler (and more economical,
    sometimes) to set up for riding/racing.
  • Back in the day, aggressive riders may have extracted more out of
    the KX and converted motocross bikes in general. I don’t think it
    was an accident that in the 1990s and 2000s, so many of the top
    GNCC guys raced motocross bikes. Now that manufacturers have
    developed hybrid bikes like KTM's XC line, there seem to be less
    riders converting motocross bikes into woods racers. But for a guy
    who’s in good physical shape and can ride hard for hours at a
    time, a converted motocross bike has its place in the woods.
  • From a strictly monetary perspective, there's a lot less reason
    these days to convert a motocross bike for woods racing. Any
    purpose-built KTM will probably cost less to make ready for
    racing. But not always. As I found with my two KX250's, a leftover
    Japanese MX bike, adequately discounted, can sometimes be
    bought and modified for about the same cost as a purpose-built
    KTM. However, if you plan to ride enduros and need lights, then in
    almost every case the MX bike becomes more expensive to
    convert to woods use.

In summary, I liked the KTM 300s because they represented the best
value for an all-around bike. Today's enduro-ready bikes are probably
even a better value, if you need a bike with lights. But if you’re an
aggressive rider, in good physical condition and want to specialize in
hare scrambles and GNCC’s, a converted motocross bike isn't the
only option by any means. But in the time before the KTM XC lineup
changed the world, a motocross conversion certainly had its place.
Updated December 2014