You could do it a few ways,,,I am not a pro, but the first way you could do this is w/ a head mod. You will have to measure stock how many cc's of trapped volume you have in the head w/ a burret tube and water. Shave off amount of desired material from the head surface,(.010 or whatever to attain desired clearance), re-check squish, recess squish if you need to, then, re-cc the head to see what the trapped volume is. Cut into the bowl and remove material to accuire stock trapped volume. I know on my ktm 03 125, the head looks very difficult to cut, I don't know how yours is, but you could also do it w/ a cylinder and head mod. KTM makes a wide variety of diff thickness base gaskets, you could buy a few of them and experiment to get a tighter squish, however, you will alter port timing w/ a thinner gasket, boosting some low end, and possibly not letting the bike rev out as far as it does now. Following the trapped volume procedure, you could also Remove desired amount of material from base of cylinder, then re check squish, etc,,,,The cheapest way to do this is to get the gaskets and check for squish. You will be able to see if you are going in the right direction w/o doing any permenent mods to you jug or head. I hope this info is accurate and helpful, post back-