Z 1000 / ZX9R Bottom end Butterflies

Just wondering if any one has remove the butterflies that restrict the engineat low revs on a ZThou or ZX9R?
They have done it at mid town on a shop Z750and one of their employees Z1000. It is to increase the 'snappiness' of the bottom end.
My main query is whether it leans the engine out to far and cause other issues. They have said it won't affect my warranty etc but i am still sceptical.

Thanks
Terry

PS pls reply with factual personal experiences with your own bike. Comments on the dealership are not necessary.

i dont beleive any such butterflys exist on a zx9r, well not mine any way


they are there to increase the air velocity at low RPM's, but open up as the revs rise to let more air in... if they are getting boosts from taking them out, then something is wrong ... tho i dunno if you can change when they kick in or not?


your fuelling setup doesnt care how many throttle butterflys you have, the injectors are going to squirt the same ammount of fuel in if you only had one big throttle butterfly, rather than 8 of them