I have a KMX 125 B12 2002 model, I have converted mine to full power, it is so easy, first take out the plastic former that holds the air filter in place and cut away as much of the plastic as possible (I used a soldering iron) but still leaving the basic external shape the same, then drill a few 10mm holes in the side of the air scoop on top of the air box, the you will need a new exhaust system, mine is made by "BIG" it cost about £150 for the whole lot.