Since they dont make flywheel weights, i was going to just weld some weights on and see what happens. has anyone ever done this? Okay, its going to be a little more technical then that. I wanted to know a few questions 1) When you buy a heavier flywheel and they advertise a +8oz, is it literally an 8oz disc? or is there some kind witchcraft math going on here to get an equivalent moment of inertia with 8oz on the perimeter? 2) has anyone ever bought a different flywheel for another bike and simply weld it on? My plan was to get 8oz of whatever my flywheel is made of (probably aluminum) and calculate the mass moment of inertia, and then find the equivalent with perimeter weights, then TIG weld those bitches on. Balance it and grind as required to get it to be as balanced as possible. good idea? bad idea? i am converting my 2012 KX250F to an enduro/hare scramble bike.