I'm about 5'9" and would gladly trade my present Superbe Pro Crank in a 170 size for a 172.5. I have a 52/42 and that's what I want. My chainwheels are in very good condition as is my crank. Any offers? leads? I am convinced that the larger size crank would help me turn the bigger gears that elude me. Would also consider buying a crank without a trade. Garth in Miami Shores Fl. (P.S. getting back into shape after a sprained wrist and a severe case of sciatica.. time heals all wounds with the help of a good chiropractor.)