My conversion is a Mystery Design Independent Suspension that way I can control the ride with air shocks. I can decrees the air if I want to go tear it up or beef it up for the wife and camper. You will defiantly see the decrease in mileage when you trike it but it to me was well worth it. As far as top end speed didn't really see the decrease at all. she still screams. just make sure you change the rake on the front not unless your a beast. I raked mine 6 1/4 and now she turns smooth rides great and is a dream. The only thing that I want to get done is a better seat then she will be done.