Joined: Feb 2005
Posts: 13,560
Likes: 44
From: Milledgeville, Georgia
Bikes: 2018 Black Mountain Cycles MCD,2017 Advocate Cycles Seldom Seen Drop Bar, 2017 Niner Jet 9 Alloy, 2015 Zukas custom road, 2003 KHS Milano Tandem, 1986 Nishiki Cadence rigid MTB, 1980ish Fuji S-12S
The real answer is N+1. My Zukas road bike has room for up to 35mm tires. I usually run 32mm tubeless tires and I'm good for anything from smooth asphalt to smooth hardpack dirt/gravel roads. My AWOL can take up to 2.1" knobbies, but I like 42mm Sawtooth tires for rougher gravel and rougher dirt.