Air Box Mod?

[Cam]

Has anyone opened up the stock air box where it goes into the motor & if so, is it a good idea?

Mine's a '99 with a K&N filter.

[Madmax]

A lot of us have done "The big airbox mod" which opens the box right up, removes the flapper valve etc.

I've just reversed mine to get my bottom end power back. Now it's a rocket bottom and top end again. I also have yoshi stage one cams, there's where some of my top end increase has come from.


Cheers


Max

[Gaz57]

Cam,
depends on what else you have done I think. Mine is a 99 with the big air box mod, pair valves blocked with the pipes and pump removed, full yoshi 4 into 1, K & N filter and powercommander. To long ago to remember if it had better botttom end, it still goes well for a ten year old bike If you are worried try and get a spare one to experiment with. You can then go back to standard if you don't like it.

[spamanglenn]

What do you call the big air box mod as opposed to the small air box mod?

[simmo]

http://www.australian-hayabusa-club.com/...p?tid=9498

[Gaz57]

I thought the small one was fixing the flapper valve open. The big one cuts the flapper valve and some of the air box out?

[Maj]

Big airbox mod usualy entails making a air filter as you cut away part of the filter mount
whats commonly called the small airbox mod is removing the flapper .

[spamanglenn]

Correct.i have a flat foam filter with gauze either side that sits like a gen2 or gixxer 1000 airbox.Only bigger. Throttle response down low is slightly softer but the torque is smoother with less lumps in its delivery.Back to back with a small airbox mod and a stock airbox it beat both of them on a dyno,mostly down low gains.At part throttle however the road feel is crisper with a stock airbox.

[Gaz57]

Thanks Maj and spamanglenn for clearing that one up. I have the small mod then .....goes with the rest of my mods

[Cam]

Thanx heaps lads for your advice. I've already done the "small airbox mod" & put in a K & N. Seeing as how no-one has any real bad news about the "big airbox mod" then I guess it'll be next on the "to do list".