This bike will take 700x32 c tires with penty of room, yet it still feels like a road bike. The big tires , handbuilt wheels and slightly longer wheelbase make this a cushy ride-important in this case as the bike is destined for the streets of San Fransisco with all of its trolly tracks and old pavement. The fork is a custom order Wound-Up made to the spec I asked for-name another company anywhere that will build you a custom carbon fork in less than three weeks .........I can't ! Other than switching out the 10 degree stem for a zero degree, this is how the finished product looks. The Ultegra 6700 group is so close in design and performance to Dura Ace that I doubt most people would be able to feel the difference, other than wieght.