Two Brothers Racing Yamaha YFZ450 Dyna FS Ignition User Manual
Page 2
Note: The Dyna FS ignition for the YFZ450 uses the stock T.O.R.S. (Throttle Over Ride System) to kill the ignition in the
event of the throttle becoming stuck wide open. The ignition requires 8 engine revolutions of a non-grounded TORS input
to determine ignition cut. If an aftermarket carburetor is used, the TORS input (Yellow/Black wire at the CDI module) can
be permanently grounded to defeat this safety feature.
Note: For grounded tether switches: The simplest installation of this type of tether switch is to connect one kill wire to the
White wire, and the other kill wire to the Red wire.
Note: For kick start applications, the battery should be left in place. The battery can be replaced with a smaller
lead-acid battery, OR the flywheel can be replaced with a higher energy flywheel from Trailtech.net (1-
360-687-
4530)
and a 4,700µF electrolytic capacitor can be installed in place of the battery.
Note: Advance varies smoothly between WOT and PT based on TPS
DYNA FS 7-12/ YAMAHA YFZ450 ATV IGNITION CURVES
Assumes 7.5° base timing
RPM / 1000
I
G
N
IT
IO
N
A
D
V
A
N
C
E
(C
R
A
NK
S
H
A
FT
DE
G
R
E
E
S
)
WARNING: Installation of a grounded tether kill switch to the ignition coil signal will damage the CDI and
void the warranty.
12V DC-CDI (YFZ450/Predator 500/Raptor 660/LTZ400/KFX400/etc.): Use a normally closed tether kill
switch connected in series with the +12V input to the ignition. When the tether is removed, it should disconnect
the +12V power to the ignition. If a normally closed tether kill switch cannot be located, then a grounded tether
can be used to ground the pickup signal (Red wire at the ignition module)
YFZ450 +12V POWER INPUT: RED/BLACK at the ignition module.
The RUN/STOP SWITCH is another +12V input into the ignition module.
2801252 REV.
4-11-06