Am a sub Clydesdale, 6'1, 195lbs, but friends say I ride like one. Average 800 miles, 60K feet of climbing a month. 2012 Specialized Tarmac Pro 58cm. Went through several sets of wheels. Previously split the rim on Ksyrium ESs. A friend gave me a pair of Mavic Open Pro 32 spoke, DT Swiss Spokes, Campy Record hubs tied and soldered running with 25mm tires 110 PSI in the back. They were built by a well known local wheel builder. Am having trouble keeping the rear wheel true. Not horrible but noticeable after a month. Have not really dropped into any holes that I noticed. Do not know enough to come to any conclusions. Is it the nature of the beast for larger guys who do a lot of riding or built true and stay true. Ridden with 2 180 lb. guys who are having problems with Zip 101s and 404s as well. Any words of wisdom?