Here's my progress so far on my 2001 TTR125 mad dog build. Started with a pretty incomplete bike, but was able to get one of motoman287's conversion kits. I had a swingarm and wheels left over from my son's YZ85, so I had a bit of a head start. Gotta keep this one at 125cc due to local rules, so I installed a high compression piston and more aggressive cam. It's getting a 24mm Mikuni, and FMF pipe. No air box. Will eventually be running 17" wheels, though I don't have a plan yet if I need to lengthen the swingarm. Suspension will be professionally set up (not by me).