INSTRUCTION SUPPLEMENT FOR 2004-
LATER YAMAHA YFZ450
Removing stock carburetor and cables.
1. Remove seat and gas tank. Make sure fuel
petcock is in "off" position.
2. Remove throttle cable paying close attention
to routing, as the new cable(s) will need too
be routed the same.
3. Remove stock carburetor and stock throttle
housing. Stuff a clean, dry rag into manifold
to keep debris out of motor.
IMPORTANT NOTE: This machine is equipped
with a throttle over-ride system (TORS) and a
neutral safety switch. You must unplug the
From the wiring harness located near the
steering stem top mount. The neutral safety
switch located on the clutch perch must also be
removed and unplugged. Once unplugged,
tape the two wires together that come out of the
1. Carefully trim the rubber alignment tab off of
the face of the manifold with a razor blade or
2. Remove the hex pipe plug from the carb cap
using a 11mm or 7/16 wrench. Do not
discard plug, as it will be needed later.
Install the metering adjustment tool included
in the hardware kit. Do not over-tighten as
damage may occur to cap.
1. Attach fuel line to carburetor and secure with
2. Place carburetor into manifold and air boot.
Tighten clamps with carb sitting as close to
vertical as possible.
Twist Throttle Instructions
1. Install the throttle cables into the supplied
throttle housing and place onto clean
2. Route throttle cables through frame as stock
cable was routed.
3. Install the pull cable into the 8:00 position
and the return cable end into the 11:00
position of the cable wheel. Secure cables
to cable bracket by replacing end piece and
Phillips screw. See figure 2.
NOTE: SEE FIGURE 1 TO IDENTIFY CABLES.
The bottom cable is the pull cable.
Thumb Throttle Instructions
NOTE: Modification of the stock thumb
throttle housing will be required in order to
achieve wide open throttle. Figure 3 will
show the mods.