Semi-Custom Open WI.DESince its inception, the Open U. P. has reigned as the pinnacle of do all gravel bikes. With its clean, minimalist lines, substantial tire clearance, and perfectly balanced geometry, the U. P. (and its even lighter sibling, the U. P. P. E. R.) quickly prevailed as one of our favorite bikes to ride. Naturally, it proved to be one of our best selling models, too. As time went on, though, and riders got used to running bigger tires, pushing the limits of