I just bought this pipe for my 2012 Honda crf100f and it sounds amazing. It beats better than the stock pipe. I would suggest buying it! I think Pro Circuit is a good pipe it sounds good. When you first take off it is just a great pipe and there product is one of the best brands but there pipes are expensive but it is worth it. I didn't need to rejet it or anything, just put a few bolts and it is ready to go!