I sported one on my 00' Yz125, a bike that would definately benefit from some bottom-end:) And I definately noticed some added torque. I think its one of those things that bike/brand specific, doesn't work for all types, but works very well of some. Its a cheap try at about 30 some bucks I believe. Like Faded said the o-ring trick works well too. I also noticed an improvement from bottom-end orinated reeds. Its all relatively inexpensive mods, do them one at a time and see how much of a difference each makes. :thumb: