What year? The newer ones have the speed restriction governed at the controller and the older ones are controlled at the display. I got a KD718 display and with that and having changed my freewheel from a 14 x 28 to an 11 x 34 I can get a top speed around 33 mph. This first YouTube video shows how you do it for the stock Himiway Cruiser display.......https://www.youtube.com/watch?v=DNwOPqtt3Fw&list=PL2PuAh4tblWEqFNxXKfkGOXJcAGQVkcT4&index=46&t=298s