I've got the 9-speed freewheel. I think it is 13-28 or 13-30. It works well on my recumbent bike, a RANS V2 Formula. I use a 7-speed when I put the kit on my mtn bike. Shifting works fine on both bikes. My particular 9-speed freewheel is higher quality than the 7-speed freewheel that I got...