More Pink Wire

[OB_Falconer]

I have a question about the end of Don's "Cut That Pink Wire! note --

<<<Thanks to several of the european listers that contacted Suzuki and confirmed the
info contained herein.>>>

The implication of this is that euro-spec bikes are saddled with a U.S. EPA-mandated noise restriction built into the ignition system of the Hayabusa.

This doesn't compute (at least for me). Why would Suzuki restrict the performance of their non-US product, especially if cutting one wire (which I have to assume comes from a gear-position switch in the transmission) eliminates the restriction?

If you were Suzuki, wouldn't you ship the most powerful machine you could into the geographic region you were shipping to?

 

[rotts4u]

Here is the "Official Suzuki reply to the pink wire removal.In other words dont do it !!


Disconnecting this wire to increase performance is a common misconception.

If you were to disconnect the gear position (pink) wire on any Suzuki EFI
motorcycle, poor performance and possible engine damage will result.

This rumor started because earlier model carbureated GSX-R1100's used a pink
wire to retard ignition timing in first gear to improve traction. Some
tuners discovered that disconnecting the wire increased engine HP output in
first gear. The motorcycle did produce more engine output with the wire
disconnected, but it became more difficult to accelerate from a stop and
actual acceleration and traction was reduced. But riders liked the "feel" of
increased engine performance.

The Gear Position Switch wire is also colored pink on the GSX1300R Hayabusa,
as it is on previous Suzuki's. Like the TL, this switch provides
transmission gear information to the motorcycle's Electronic Control Module
(ECM).

Some mechanics and consumers have experimented with disconnecting this wire
to improve performance or drivebality (especially during the very early
TL1000S driveablity problems before Suzuki released the improved, revised
ECM).

As the rider selects higher gears, the ECM changes the injector duration,
usually longer, producing a richer mixture to compensate for the additional
air provided by the SRAD ram air system. Without the additional fuel, the
mixture will become lean, performance will deteriorate and engine component
damage is possible.

Since a disconnected gear position wire will make the ECM think the
transmission is in neutral, the injector duration is longer than it might be
in the first couple of gears.

This is why the customer might feel a "seat of the pant" driveablity
improvement".

A mechanic using a Dyno may see different, or improved HP with the wire
disconnected.

BUT, since the dyno is testing a static motorcycle without a pressurized air
box from the ram air system, the results do not indicate real world
performance. A fully operational EFI system on a dyno will indicate lower
peak power as the mixture is slightly rich. Disconnecting the "pink wire"
will lean the mixture to a better level for a non-moving motorcycle.

Once again, leaving the wire disconnected will reduced on-the-road
performance and could lead to engine damage.

 

[OB_Falconer]

I can see I was being unclear in the point I was trying to make -- is it possible that there was some overall engineering reason _besides_ noise control for reducing the output of the engine in certain RPM / gear regimes? And that by cutting the pink wire you might be putting some mechanical aspect of the machine at risk for premature failure?

Just a thought.

 

[rotts4u]

First of all I would not suggest that ANYONE do the pink wire mod until we get the technical details worked out to confirm or deny the engine failures that it is reported to cause.

Now as far as the US vs Europe bikes I assume that Other countries also have noise and or pollution regulations to contend with. In fact some countries have cat convertors in them stock on the Hayabusa.

Don

 

[OB_richie]

I put the pink wire back went for a ride didn't seem to feel any difference in power,the engine did sound more quiet with it on then off,I will keep testing and let you known richie ps. It flys with it and without it, case closed,