The specialized roval traverse 38 sl fattie carbon clincher 650b wheel set the new age of traction stability and speed has arrived and its name is the roval traverse 38 sl fattie 650b wheels they feature 148mm rear and 110mm front axle widths but to turn them into descending machines is the 38mm internal rim width the extra width also allows for more tyre volume which means increased suppleness in the ride quality and not only this but the ample width also better supports the tyre meaning th