The top gear on my mountain bike is 48/12 with 26" tires = 104 gear-inches, but I am perfectly happy with mid-90s on my road bikes, with 50/14 or 46/13 (~96) being my favorites. I go as low as 49/14 or 45/13 (~94) for a top gear on two of my other road bikes, but have spun out when I tried anything less, such as 52/16 (~88), in the past..
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069