2019 Dynamic Pro XR - should I disconnect the ‘flapper’ wires?

[Beemah]

What are flapper wires? What are the pros/cons of disconnecting them on my 1st Gen dynamic pro? How do I do it?

Some guy on Reddit just posted a picture of his new, 2nd Gen XR and said he just took the flapper wires out for a little more noise out of the exhaust. I have never heard of this, so I looked it up and am intrigued. What exactly is it? How does it work?

[Antares]

"Flapper wires" refer to the bowden cable  that actuates the exhaust valve via a servo motor. Disconnecting them will simply mean the exhaust flap is always open by spring tension and therefore more noise. On the gen 1 there is some difference but it's not massive.

Pros:
More noise
Maaayybee better power/response down low

Cons:
More noise
Slight possibility of exhaust valve slamming shut at high RPMs due to exhaust flow, I recommend security wiring the exhaust valve so it's locked open.

It doesn't damage or affect the bike in anyway apart from this. It will throw a hidden code on the Gen 1s but no warning triangle so I wouldn't worry.

[Beemah]

All I could find on the topic was this video, removing the servo from a 2016 RR. Seems simple enough, does the muffler have to be removed for this? How do you make sure the flapper is in the 'off' position?

[smithy]

Just disconnect the cables, pretty simple. The valve "defaults" to.... and is spring loaded to open. As Antares says, it will throw a fault code but not a fault light.

Smithy.

[Beemah]

Originally Posted by smithy

Just disconnect the cables, pretty simple. The valve "defaults" to.... and is spring loaded to open. As Antares says, it will throw a fault code but not a fault light.

Smithy.

The best info online I have been able to find regarding this mod is your post. Just disconnect the cables - I will zip tie them to secure them.

[smithy]

Originally Posted by Beemah

The best info online I have been able to find regarding this mod is your post. Just disconnect the cables - I will zip tie them to secure them.

Ideally you should remove the cables and servo itself and fit a servo buddy....but tying the cables up out of the way will work, you'll just get a fault code as the ECU will think the servo is not working properly. The "stop & start" points of the servo will now be different to when it was fitted at the factory, hence the fault code.

Smithy.