It runs good man. I just put on a 52 tooth sprocket about 10 minutes ago. It's about 4 in the morning now lol. I'm really hoping this will improve the low end quite a bit. I'm not real worried about goin "fast" but gettin goin from a dead stop with less effort will be nice. I'm pretty sure I can still get at least 20mph out of it with the large sprocket which is fine for me because that's pretty much the speed I like to cruise around at. I live in a small town with a lot of hills and even hills directly after a dead stop so this will be nice if it works like I hope. I'll let you know