I have a question in regards to the Vittoria...
I have a question in regards to the Vittoria Ultralite Tube. Will the 42mm valve stem fit a Rim depth of 27mm? That will leave me with 15mm left on the valve stem. This should be enough stem length to get the pump on, correct? Don't want to order the 51mm stem lenght if I don't have to.
42mm will leave you with plenty of stem leftover for airing up.
Also, remember that a rim depth of 27mm is measured from the top of the braking surface to the bottom of the rim. The tube sits inside the rim and thus the valve body starts inside the rim. So you'll actually have more than 15mm of valve stem sticking out of the rim.