hiya the top speed of nsr 125 rr wich i own is 110mph but its a jap import my friend owns a rs 125 and he cant keep up very well on acelaration or top end speed i also suggest lookin into a cagiva mito a friend has 1 of those 2 its a top ent speed of 120mph fully d-restricted i suggest the best 125cc but not very reliable wen runnin d-resticted