The 02 CR125 motorcycle is really down on power compared to the our 125's in the class. Our pipe was designed with the Plano Honda Race Team, and gives the bike better bottom, mid, and top end power. You will noticed the biggest difference in mid to top end which most riders use the power. I am not sure how it is going to work because I don't know what has been done to your engine. Also, you need to buy the 02 pipe and I would buy one of our exhaust flanges. They work with our pipe really good!!!