CYLINDER WORKS / FACTORY CONNECTION YZ269F

RACE TEST
CYLINDER WORKS /
FACTORY CONNECTION YZ269F
MAEDA
R: BRENDAN LUTES
I
Clark handed the Kayaba suspension comn 2001, Yamaha produced the first 250cc
ponents off to Factory Connection with orders to
four-stroke and further advanced the
rebuild the forks and shock for a 160-pound Interthumper revolution. The small-bore machine
mediate level rider. The stock spring rate of the fork
was revolutionary at the time, but in the 12 years
was kept, but to allow them to settle into the initial
since its unveiling, its powerplant has undergone few
part of the stroke as well as improve the absorpmajor changes. This lack of change, coupled with the
tion of small bumps and harsh hits, the valving was
number of advances made by the competition, has
changed and a 1.7 pressure spring was installed.
left the YZF in the dust. We’ve become accustomed
Other minor internal parts were changed, with the
to the YZ250F and its nuances, but more importantly,
most notable being a modiwe’ve created a list of necesfied bending check valve. This
sary enhancements to bring the
All of the modifications
part allows the forks to sit
YZF up to speed.
higher in the stroke, which is
In stock trim, the YZ250F is
worked together to allow the
the sweet spot where they pera great bike, yet there is room
bike to breathe better and in
form their best. The shock refor improvement in both its enceived many similar changes,
gine and handling. For starters,
turn produce more power.
and FC started by softening up
the bike is the lone four-stroke
the low-speed compression.
to be carbureted, which reWhen combined with a different compression pisquires exact jetting and tuning to achieve the most
ton plate, these changes give the bike better hanhorsepower possible. Yamaha updated the chassis
dling over rough, square-edge chop. The revalved
and suspension in 2012, and while it was an imsuspension offers a ride that is plusher and forgivprovement, the forks and shock remained soft and
ing, yet still withstands hard impacts and landings.
underdampened.
We handed our 2013 YZ250F test bike to bike
building specialist Jay Clark and requested it receive
ON THE TRACK
the full treatment. Clark started on the engine by inOnce we took delivery of the completed machine,
stalling a Cylinder Works 269cc big bore kit, includwe immediately noticed how easy it was able to
ing the supplied Vertex piston and Cometic gaskets.
come to life. All of the modifications worked toMarketed to Vet class racers, the kit is also the pergether to allow the bike to breathe better and in
fect way to cheat—which we in no way condone—as it
turn produce more power. Because the YZ250F is
leaves no visible evidence on the outside of the cylincarbureted, it is known for experiencing a slight bog
der. To complement the additional cubic centimeters
off hard landings or when throttled hard off of idle.
and achieve even more power, a Hot Cams Stage Two
We experienced the dreaded bog out of corners on
system was added. The stock air boot was swapped
our initial ride but raised the needle to the fourth
for a MotoTassinari Air4orce intake, which tailors
position from the top between motos. This change
the power to a rider’s needs by altering the airflow
allowed us to finally truly critique the complete
through interchangeable stacks placed inside. To
package. The changes to the gearing permitted us
complete the overhaul, we mounted a FMF RCT 4.1
to stretch each gear farther, making it easier to go
silencer and Megabomb header, dropped two teeth
faster without losing the initial low-end pull. The
off of the rear sprocket, and dialed in the jetting to
engine produced plenty of usable power that never
accommodate the massive list of changes made.
signed off down even the longest straightaways.
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When it comes to suspension on the stock YZ250F, the forks are some
of the best in the class, offering good bottoming resistance and great
high-speed stability. What we didn’t like about the stock suspension
package, though, was the fact that the shock and forks do not work well
together. The shock feels soft and uninspiring, which affects the performance of the forks. Thanks to changes made by Factory Connection, the
YZF had a much firmer feel and gave better feedback to the rider. While
the forks and shock were both initially plush, they didn’t blow through
the stroke and did a good job at soaking up harder hits. The suspension
allowed the bike to settle into corners better, as the bike didn’t knife or
push and actually grabbed ruts without losing traction, giving confidence
in almost any corner. Because we were able to shift into the next higher
gear without losing drive, the suspension was able to settle and the bike
handled much better.
WHAT WE REALLY THINK
YZ269F SPECS
If you are looking for a way to boost the power and overall performance
of your YZ250F, you should strongly consider following our lead with a
Cylinder Works kit and Factory Connection suspension updates. FC did
an excellent job at fixing the flaws of the stock YZF, while the oversized
cylinder and piston helped the bike produce more useable power for a
fraction of the price it would cost to build a full and legal race engine.
How you use these parts is up to you.
PROPER JETTING SPECS
cylinder-works.com
factoryconnection.com
fmfracing.com
vertexpistons.com
hotcamsinc.com
PARTS LIST
MAIN JET
LEAK JET
PILOT JET
FUEL SCREW
NEEDLE
CYLINDER WORKS 269CC KIT
HOT CAMS STAGE TWO CAMS
FMF RACING EXHAUST
MOTOTASSINARI AIR4ORCE
CV4 RADIATOR HOSES
FACTORY CONNECTION FORK VALVING
FACTORY CONNECTION SHOCK VALVING
172
55
45
2.5 TURNS
FOURTH POSITION FROM TOP
WITH YAMAHA 5TA-14916-PS-00 NEEDLE
$499.99
$184.99 EACH
$314.99 (MUFFLER); $314.99 (HEADER)
$298
$95.99
$216.90
$207.90
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