Velocity stacks?
 

me again :)

bought some spare carbs as mine are crusty :s and they are identical to my 1997 carbs except for the velocity stacks.

stacks 1&4 are shorter than stacks 2&3

on my 1997 carbs and my friends 96 carbs all stacks are of equal height.

so anybody know why? have i stumbled upon some go faster stacks ;)?

seriously though these were sold as 1997 carbs and cant be if stacks are different, but they are very clean and no crust at all :) bonus.

Short stacks are for top end power and long stacks are for mid range. 06 cbr 600rr come that way stock but some guys go all short or leave them alone. You'll see aftermarket velocity stacks for newer bikes and they're usually expensive as hell. All for 1 or 2 hp on top and no notice loss in midrange.

You can check the numbers on the carburetors against this list to determine what year they're off of. Then you'll know what you're dealing with.

A = 49 State
AC = California

Attachment 32534
Attachment 32535

thank you but that wont be of any use :( im in the UK and they are off a uk bike

All short runs better on top end.

I have 96 carbs and I have the two short and two tall.

thanks guys i ended up using my 97 v stacks just to make sure

1997 carbs were 60HALO*

unknown were 60AAKB*

the * isnt actually a star its a funny shaped + sign looks like a messed up t or f