The question is not which to buy, but rather which to keep?! I have both bikes, a 2005 CRF 100 and a 2002 TT-R125. Both need some love, they will be rebuilt and gone through but which would be the better bike for my 12-year-old daughter? She fits on either bike so that isn't really an issue. She is a beginner rider with little experience. I would have her ride both bikes except there's too much snow on the ground here for that. I'm more concerned with reliability and addressing the shortcomings of each bike. If you had to choose which one would it be?