Amsoil 10w 40 is what I have used and for the same riding conditions. street and dragstrip. For hard use I would recommend a full synthetic motorcycle specific oil and I recommend the amsoil but if price is super important try out rotella 15w 40 diesel or there synthetic 5w 40 diesel there cheap and i heard of some people using that with good results again i recommend amsoil 10w 40 as your first choice though........