My 2005 Yamaha YZ250F will only
run when the choke is on. What’s
We assume that your bike has
been sitting for a long time with old
gas in it, or you don’t change your
air filter very often. Either way, you
need to take the carb apart and clean
the jets, especially the pilot jet. They
are either varnished up from old gas
or have dirt in them. By using the
choke, you are bypassing some of the
carb circuits. Do a thorough job and
your bike will run without resorting
to choking it.
2014 UNADILLA – MOTOS 1 + 2
This is what championship-winning
air filters look like.
They’re a few of the Twin Air filters
that Team Red Bull KTM used on their
way to take 1-2 in the 2014 Lucas Oil
Pro Motocross Championship.
In fact, this year Twin Air
won 23 of the 24 motos
in the 450 class.
THE CHOICE OF CHAMPIONS
STRONGER THAN DIRT
How do the Pro riders and MXA
test riders keep their gear so clean.
The plastic on my boots turns yellow
and the colors in my jersey fade, but
the stars always look perfect. How
do they do it?
Factory racers and MXA test riders
always wear new clothes. The gear
companies spend hundreds of thousands of dollars on promotion, and
they don’t want Ken Roczen to be
photographed with a big grape-juice
stain on his jersey from lunch. Thus,
the gear companies budget a specific
number of sets of gear per rider per
season. It is one of the perks of the
job. Privateers only get a few sets of
gear for a whole year.
WHO DOES THE WORK?
Who paints MXA’s helmets? I
look in all the catalogs to see if
those paint schemes are available—
without MXA’s logos, of course—but
I’ve never seen those styles from
the helmet companies.
Troy Lee designed the original
MXA orange helmet back in the
1990s and hand-painted the vast
majority of the helmets we used over
the years. Over the last five years,
the helmet manufacturers paint the
helmets for us. Sometimes they are
based on any existing paint scheme
from their product line, but since
we need the color palette to be
primarily orange, they aren’t easily
recognizable as an existing factory
paint scheme. ❏
THE PERENNIAL AVGAS
My friend runs Avgas in his
KX250F and says that I should too. I
hear both good and bad things about
aviation fuel. Does MXA run Avgas?
Jody does run 100LL (Low Lead)…
in his airplane, but not in his bike.
MXA has nothing against running
Avgas in bikes, but it isn’t going to
be as good as fuels designed specifically for four-stroke and two-stroke
machines. Avgas’ big pluses are
that it contains lead and no ethanol.
Although we know lots of racers
who run a 50/50 mix of Avgas and
premium gas in their two-strokes, if
it was us, we’d prefer to run a 50/50
mix of VP C- 12 and pump gas. If you
have a stock four-stroke engine, your
bike will run fine on fresh high-test
premium pump gas.
Looks new, is new.