I bought a number 2 tune on my Roxor thinking that it would solve my 45mph max problem and give me more power. Yes I got up to 76mph but I heard a not quite a whistle but not just nothing to ignore. So I ignored it because I had some power and was able to go up to 76mph. That was good enough for me because I got legal to drive. That’s awesome. But driving it around on the daily it was week, even with a 2 stage tune. So I broke down and ordered the “intake connection kit”. Yes they advise anyone that up grades to get one. I thought it was a sales gimmick. I heard the hhhiiiissss. On my machine. So I order and put it on thinking hell I spent more money on beer than that lol. After I installed the new connection kit I drove my machine. Holy €£it my Roxor was a whole new machine that I didn’t know existed. I don’t care if you tune your machine but I highly recommend getting the boost connection kit. It is worth more than the tune!