engineers back in Austria were adamant that it would
work (they also told us that they hadn’t tried it themselves, which only increased our trepidation over such a
lean mixture). But, Husqvarna assured us that if we blew
up our engine with the factory-recommended 60:1 ratio,
they would put all-new parts in our bike. So, we put
the jetting back to stock and drew straws to see who
would ride the 60:1 time bomb. The bike ran perfectly.
No hiccup or sputter.
The problem for both Husqvarna and KTM is that
no one ever reads the owner’s manual. Add to this the
old-school mentality of most two-stroke riders, who are
stubbornly resistant to change, and we don’t see a lot of
250SX or TC250 owners risking their engines on a single
line in a book. Plus, they don’t have factory mechanics
promising to rebuild their engines if they are wrong about
the fuel mixture. Nevertheless, the ratio is right. It worked
and made us change our opinion about the Mikuni-for-Keihin swap of 2017.
ON THE TRACK, OUR BACKYARD
TC300 FELT HEAVIER THAN THE
TC250—HEAVIER THAN CAN BE
ATTRIBUTED TO THE 7-POUND
WEIGHT DIFFERENCE BETWEEN
On the track, our backyard TC300 felt heavier than the
TC250—heavier than can be attributed to the 7-pound
weight difference between the two. While our Vet and
Novice riders didn’t notice much of a difference, the faster riders were quick to mention that when picking a line
or maneuvering, the TC300 felt heavier. No matter how
you slice it, 7 pounds is significant, but why didn’t the
slower riders notice the weight, while the faster riders
did? That’s simple. The 300cc engine produces a different
kind of power than its snappy 250cc brethren. The bigger
engine’s torquier vibe gives the bike a heavier feeling.
Think of it this way: a 2017 KTM 450SXF weighs less
than most Japanese 250Fs, but it still feels heavier on the
track due to the power pulses of its bigger displacement.
When you add in the chug effect of the larger displacement and heavier flywheel, the rear end of the TC300
sticks to the ground like glue, whereas the TC250 hits
hard, jumps at the slightest hint of throttle and feels light
as a feather. Of course, the main reason the TC300 feels
heavier is that 7 pounds is 7 pounds, no matter what
scale you use.
The biggest difference in handling goes back to the
heavy feeling of the bike. Many of our test riders, even
the Pros, loved the four-stroke-like tractability of the
TC300. It was foolproof. It didn’t matter how hard you
were on the throttle, the rear end would squat, track to
the ground and follow the front wheel like clockwork
every time, almost like traction control. It was the best
of both worlds—the good-handling traits of a four-stroke
mixed with two-stroke flair.
The switch from the offroad TX300 suspension to the
TC250 suspension components allowed our testers to
access the full potential of the TX300 on a motocross