Not sure if i'm digressing from the OP question, but I have a surly cross check. I mount my topeak road morph along the seat tube but behind from the corner where the chainstay and seattube meet and the seattube and seatstays. It fits fine on a surly cross check without fenders. Then on my steel road bike, I can either mount beneath top tube or from corner where chainstay and seatstay meet and seatstay and seattube meet. Topeak has lifetime warranty too! Or maybe that was Blackburns..