WHAT IS IT? Used by the Dixon Yamaha GP team,
Twin Air’s YZ450F Powerflow kit does double duty by
improving throttle response and providing a better seal
between the air filter and intake tract.
WHAT’S IT COST? $259.95.
CONTACT? www.twinairusa.com or (800) 749-2890.
WHAT STANDS OUT? Here’s a list of things that
stand out with the Twin Air 2014 Yamaha YZ450F
(1) Concept. We were overjoyed that Yamaha
completely redesigned the 2014 YZ450F intake scoops
and airbox. The previous-generation YZ450F intake
tract—from the intake scoops to air-filter design and
configuration—was over-engineered and under-developed.
Twin Air made a Powerflow airbox kit for the 2010 to
2013 YZ450Fs that used a completely different air filter,
airbox and intake tract. For the 2014 YZ450F, Twin Air
didn’t take such a drastic approach. Instead, they focused
on improving the interface between the intake tract and
the air filter by crafting a rigid, aluminum sealing ring
and filter cage. It is a much simpler design.
( 2) Stock configuration. The MXA wrecking crew
has noticed that excessive dirt collects at the base of the
stock air filter, where the filter touches the plastic base
plate. This dirt can push through the filter. Twin Air’s
sealing ring moves the filter/cage assembly upward to
keep it away from the base plate.
( 3) Backfire screen. In a nice touch, the Twin Air
Powerflow sealing ring doesn’t use a backfire screen. But
to be safe, Twin Air filters are chemically treated with a
( 4) Installation. Although installing the Twin Air
Powerflow kit on the 2014 YZ450F was considerably
easier than last year’s model, it wasn’t without issues.
We had to remove the shrouds and seat and turn the
gas tank around to access the airbox. Then we had to
remove the airbox’s bottom plate to reach the sealing
ring’s mounting screws. The process was fairly easy,
but we had difficultly installing the Twin Air aluminum
sealing ring. There’s a plastic tab at the base of the
airbox that must be filed down a few millimeters in
order for the ring to fit. Once that was done, we had no
further trouble installing the kit.
( 5) Performance. We liked the Twin Air 2014
Yamaha YZ450F Powerflow kit because it eliminates
the backfire screen, eradicates the annoying whirring
sound that the stock air-filter cage/sealing ring makes,
and provides a much better seal between the ring and
WHAT’S THE SQUAWK? We took issue with the fact
that the Twin Air sealing ring didn’t fit into the airbox
If you are serious about getting the most out of
your 2014 YZ450F, the Twin Air Powerflow kit
should be on your short list.
TWIN AIR 2014 YZ450F POWERFLOW KIT
MXA TEAM TESTED