Flies out??? Secondary Butterflies on a Gen2?

[Corso1]

All-

I was jumping around the forum the other day, and saw a reference someone made to pulling the secondary flies out of their Gen2 Busa? Having had a ZX14, this is pretty common for the Kaw, and the improvement in throttle response is immediate and almost violent. But... I had never heard any reference to doing it to a Busa. Figured it would have been as hotly discussed here it is on the 14 forums if it were a common mod. I haven't even bother to look for myself, but thought I would throw it out on here. Has anyone heard of this for the Busa?

FYI. It is so common on the Gen1 ZX14 that Brock's even sells two completely separate TREs for that machine. One if you retain the flies, and the second if you pull them.

Anyway...figured I'd ask.

 

[BusaBret]

Here is some reading on the subject...

https://www.hayabusa.org/forum/gen-...004-secondary-butterflies-removal-review.html

From my dunce stool :cookoo:

 

[Corso1]

Thanks Bret!

Must not be too popular...41 looks and only one reply. I'll check out the link.

Much appreciated.

 

[Ludicrous Speed]

I have a friend that did it, and the bike seems smoother when launching at the track, but you can do the same thing electronically through ECU editor

 

[mestona]

...you can do the same thing electronically through ECU editor

This is how I did mine, the theory is that they help smooth the airflow into the head at low RPM and when fully open offer negligible restriction to the airflow at high RPM. I have mine set to 94% (max setting) from idle on up in ECU editor. The other reason I didn't want to remove them is the possibility of using them for traction control purposes later when the software is developed.