and just thought they all lacked a little something. I
found myself wanting
more response off the
bottom, with a stronger pull into
and through the midrange. The
YZ250 has good top-end power, but
if I could find more up there, I wouldn’t complain,” commented Doug
Dubach. He also added,
“The NS- 2 system for the
YZ250 was one of the
most difficult and time-consuming exhaust
systems I have ever
developed.” A Barnett
Dirt Digger clutch was
installed to improve the
long-term durability and
help with transferring all
the newfound power to the
ground. Barnett combines a billet aluminum basket and
pressure plate with steel inserts in crucial wear areas.
The machined oil passage windows allow more oil flow
for cooler operating temperatures and longer clutch life.
Two-strokes are notoriously busy in the handling
department compared to modern-day four-strokes, so
Dubach turned to Factory Connection to calm down the
YZ250. In the rear, Factory Connection completely went
through the shock. Besides a revalve, the high-speed
compression adjuster spring was changed to a slightly
softer version, and a Factory Connection KYB shock-
compression piston plate was installed for more oil flow.
For the fork, a 1.7mm pressure spring was installed, and
the oil level was lowered to reduce harshness. Factory
Connection also softened the low-speed compression
valve stack and increased rebound damping for
improved traction. The goal was to give the YZ250 a
plusher feel than most motocross bike with a good resis-
tance to bottoming on big hits.
When it comes to bolt-on parts, there is an abundance
of products available for the YZ250 two-stroke. All the
parts Dubach bolted on served one of four purposes:
making the bike lighter, faster, stronger or added comfort. Heading up the lighter department is Lightspeed
carbon fiber components with their rear chainguide, glide
plate, case saver and rear caliper guard. The trick look of
carbon fiber never hurts either. An Applied Racing complete R/S black-anodized triple clamp set was installed
by Dubach. The R/S clamps have a unique design, offering both solid- and rubber-mounting capabilities.
Urethane elastomer bushings made of an abrasion-resis-tant formula that can withstand over 2200 pounds per
square inch provide vibration-damping characteristics.
The elastomer bushings are contained in machined
pockets on the top clamp and are accompanied by
stainless steel collars. Applied also provides a set of
6061 aluminum bushings that mount in the same place
as the elastomer bushings and create a solid-mount system. ODI Controlled Flex Technology handlebars and lim-ited-edition, soft-compound, half-waffle white grips were
installed for added comfort. ARC Racing’s folding composite brake lever and RC- 8 clutch-perch assembly add
adjustability and are almost indestructible. A RK 520
MXU lightweight gold motocross chain teamed with
Sunstar sprockets, front and rear, would help get power
to the ground.
Here is the stock 2013 YZ250 before
the crew at DR.D got ahold of it.
The Barnett Dirt Digger
clutch and Torc 1 products not only look good,
they added great durability as well.
Eagle Light hubs, black
spokes and Dirt Star
rims gave the YZ a killer