FUEL CUT IS THE ROOT CAUSE OF JERKY THROTTLE
Smooth throttle control cannot be achieved without disabling this, however
disabling this alone does not always give a smooth throttle.
Ignition and fuel adjustments need to be correct at small throttle openings
"Fuel cut" happens when you release the throttle anytime above
a preset rpm that is programmed into your bike's ECU, in other words...
the injectors will stop during decel. (when you release the throttle)
effectively turning the engine off....
just the same as if you turned the igniton switch off.
*****You can test this yourself by putting your
bike in 3rd or 4th gear and bring it up to appx 60 mph and release the
Then while the bike is slowing down, just operate the kill switch on
the right handlebar "off to on" repeatedly (without
touching the throttle)
You will find that there is no effect from this because the engine is
Upon re-application of the throttle, there
is a time delay as your injectors start back up, and the time it takes
to re-wet the intake tract, and combustion chamber.
This can easily bee seen in the videos as well.
The rider feels this as a delay and jerky response from closed throttle....
This is especially important while leaned over in a turn or trying to
re-apply the throttle from the closed position.
Fuel cut can also be heard and seen with an aftermarket
exhaust as a loud pop/bang/flame and jerk when the injectors come back
on as you re-apply
the throttle from the closed position.... as can be seen in the videos
Bikes with stock exhaust and/or catalyst still in place may not see
the or hear the flame/popping,
but the throttle feel and behavior will still be the same as in the
The reasoning behind shutting the fuel off on decel (basically turning
the engine off) is:
If the throttle is closed, then why keep the engine running?
The sole purpose of fuel cut is for reducing emissions.
When the fuel is turned off, engine braking and
throttle tip-in cannot be adjusted because the engine is not actually
To be running, an engine needs 3 things, fuel, air and ignition....
If you remove any of these 3 things, the engine isn't running.
This is why when the injectors stop, it's the same thing as if you turned
off the key, or the kill switch.
So, with stock ECU programming, or programming
that has not disabled fuel cut, you
are actually turning the fuel on and off with the throttle
as you decel and re-apply the throttle.... This can easily be heard
and felt while you are riding, and is demonstrated in the above videos.
No amount of fuel adjustments, cable adjustments, or replacement throttle
tubes will solve the jerky throttle response that fuel cut causes.
They cannot do this because the engine isn't running during decel.
You can ALWAYS feel it when the injectors stop and restart every
time you close and re-apply the throttle when fuel cut is enabled.
I have included diasbling fuel cut for your bikes
in all my ECU programming that I offer to you.
As a result there is a very marked difference as to how much better
the entire bike responds and behaves under any riding condition....
This includes all aspects of handling and changing gears because the
bike doesn't pitch back and forth on it's suspension as you turn off
and restart it again...every time you manipulate the throttle.
Transmission shifts will be a lot smoother because you can create a
"neutral throttle" load, and take the load off the transmission
They move a lot easier when there is no load against them.
Fuel cut just takes all the fun out of enjoying being leaned over in
a corner trying to re-apply the throttle without upsetting your line,
your concentration while trying to manuver in traffic quickly, or your
passenger banging their helmet into yours when changing gears.
By us disabling fuel cut, your bike is
transformed into a perfectly smooth and predictable ride under any riding
and the rider can pay more attention to where he/she is going rather
than how carerfully the unpredictable throttle is re-applied.
All models will benefit from no loud backfiring and jerky throttle upon
throttle re-application when this annoyance is disabled.
All FCE products are discontinued - No longer available
We now include this feature in all of our ECU