Note: This conversion changes the OEM Honda XR/CRF50 handlebars from 3/4" diameter to standard motorcycle/bicycle 7/8". This throttle, cable, and carb top are a special design to work with the super short slide of the OEM Keihin 13mm carb. If you have a larger aftermarket carb you will need a different throttle and cable (consider our carb kit throttle and cable). The throttle, cable, and carb top SHOULD fit the 1979-1999 Honda Z50R OEM carb - but you will have to figure out how to change the Z50R handlebars to 7/8" diameter. The tripleclamp in this handlebar kit does not fit the Z50R and BBR does not currently offer one that does. If you have a Chinese knock-off of the Honda CRF50 or the Z50R you are on your own. Most likely, none of this stuff will fit.