BANSHEE 400cc POWER-VALVED “POWER UP KIT” By FMF
This is the most serious bolt-on performance mod
that you can make to your Banshee! Designed and
manufactured in the USA, the FMF Power Up kit
consists of an entire cylinder, head with
interchangeable domes, pistons, rings, gaskets,
studs, intake manifolds, reeds, reed cages and
new integrated power valve system that bolts
onto the Yamaha 350 Banshee.
gains are had via new larger Mono cylinder design for
larger transfer volume, which aids in tremendous power
gains everywhere! The larger 68mm bore gives increases
displacement (making it a 400) for greater horsepower.
Seven transfer ports are larger, aiding to port size,
which increases intake volume to feed the larger bore. A
larger reed cage area, which houses current YZ 250 reed
cages eliminates intake restriction allowing for greater
throttle response along with a broader power delivery.
Too, there are additional intake boost ports for
increases intake charging and therefore enhanced
main exhaust port per cylinder with an auxiliary sub
port, boosts the overall power output without
sacrificing torque. With the addition of a variable
exhaust port (Power Valve), the port height alters to
increase low-end performance while allowing for greater
exhaust port areas when the exhaust valve opens to boost
mid to top-end power.
Forged ultra light flat top two ring pistons give
stronger acceleration and greater top end power. The
aluminum exhaust flanges are removable and hard anodized
with an o-ring seal to reduce wear and cracking from the
pipe flanges (common in the stock system). Heavy-duty
4130 Chrome-Moly cylinder head studs will eliminate
stretching and the billet aluminum head comes with a set
of pump gas compatible 10cc interchangeable domes, with
the option to run 8.5 cc or 7.5cc domes to allow for
compression changes and adjustments when switching
The Power Up Kit comes with the following parts:
Reed Valves, carbon fiber reeds, intake gaskets,
billet aluminum intake manifolds, stainless steel
bolts & washers
Base Gasket and o-rings
68mm ultra light forged flat top pistons with
lightweight wrist pins, rings and clips
Billet aluminum head with one set of 10cc domes
Cylinder head studs and capped nuts with copper
Hard anodized aluminum exhaust flanges with o-ring
Complete Exhaust valve housing assemblies.
Price $1999.95 (price subject to change)
FMF Power Up Cylinders require the use of Keihin 35mm
carburetors with EEK needles in the 2nd
position, 142 main jets, and 42 pilot jets.
Aftermarket air filters will be required with the
use of these carburetors.
FMF will be offering a Honda FourTrax 250R Power Valve
“Power Up Cylinder” after the first of the year.
For more information contact:
18033 South Santa Fe Avenue
Rancho Dominguez, CA 90221-5514