My Hobbit with a Proma pipe never did more than 36 on flat even with some minor tweaking elsewhere. Upgraded reeds are a game changer. I'm curious about one thing before I recommend DR. Are you running the stock air filter? If so, pull it and see what happens. Even further no stock filter and then plugging one or 2 of the 3 intake tubes changed the game, I'm not kidding. I'm not completely sure why nor do I care but try it. I just DR'd mine and it's a whole different bike. But...it's a full commit. You could just slap on the kit and hope for the best with the crank etc but it's more like DR plus this that and the other thing, a commitment with labor and money. Was worth it for me. I wouldn't expect to hit 50mph right away with a DR. Mines at 42 but not broke in yet. There are benefits to just being happy with what ya got.