Thanks everyone. I've been riding the Conti Gatorskin Sprinter tubulars, 23. Of course, put 2 oz of Stans just in case. Honestly, not sure how much clearance I have on the Madone to fit 28's, it definitely fits 25s. Don't even know if there is a 28 tubular road tire? Right now, with the long commute, I'm thinking a fast tire and all my wheels are tubies right now. I've had no issues at all yet, just thinking long term. Thanks again, great info.