DR.D focused on making the power more manageable. They left the engine stock and tweaked the power with a DR.D pipe,
different mapping and an Injectioneering throttle body. It took a bit less bite out of the dog, which we liked.
nly those who have been hiding under a rock
haven’t heard all the commotion about the new
2014 Yamaha YZ450F. Doug “The Doctor” Dubach
knows Yamahas better than anyone on the planet. Not
only was he a Team Yamaha factory rider, but he is also
their official test rider and the owner of the aftermarket
exhaust company DR.D. He is clearly the go-to guy when
it comes time to iron out the wrinkles on a 2014 YZ450F.
In stock trim, the YZ450F has the most powerful
engine in its class. At just over 58 horsepower and
armed with a hard midrange hit, the YZ-F engine has
more than enough pony power for anyone who swings
a leg over the saddle. But—and there is always a but—
for the majority of the MXA wrecking crew, the stock
YZ450F powerband was too abrupt off the bottom. It felt
jerky at tip-in and needed a more unified transition into
the midrange. We wanted a more usable powerband off
the bottom and an easier-to-ride transition from the low
to the mid—and that is exactly what DR.D gave us.
You may be wondering how we can complain about
a powerplant that pumps out so much horsepower, but
until dynos go to the starting line in place of riders, dyno
numbers can’t tell the whole story. Doug understood our
complaints and knew that the power didn’t need to be
increased, just moved around to make it broader.
To improve the handling characteristics, DR.D installed a
radiator lowering kit, which lowered the radiators by 24mm.