Today while doing my Communte to work , I had a flat , Basic snake bite. get out a replacement tube that I carry it a brand new 700X20 Tube. I un roll it and it is a Schrader valve ? who in there right mind would run a schrader valve on that narrow of a tire ? Since I was commuting I also carry a spare tube n my Back pack. and that had a presta vavle on it so all was good.