Joined: Jan 2009
Posts: 44,160
Likes: 6,381
From: New York, NY, and High Falls, NY, USA
Bikes: 1962 Rudge Sports, 1971 Raleigh Super Course, 1971 Raleigh Pro Track, 1974 Raleigh International, 1975 Viscount Fixie, 1982 McLean, 1996 Lemond (Ti), 2002 Burley Zydeco tandem
One inch is a decent rule of thumb, useful for many people on road frames, though it doesn't have to be a hard and fast rule.