I've always estimated the size of a frame by eyeballing the length of the head tube. But I have a Carlton Catalina that has an 8" long HT and 24" ST and a Schwinn 11.8 with 8" HT and 25" ST. I guess the geometry makes a difference to my method in that the 11.8 must have steeper angles?
Thanks in advance to all who respond.
Jack Romans
Sacramento, CA