Originally Posted by Sheldon Brown
Talking about just one end of the system is not all that useful.
For instance, many cheapo department store "mountain" bikes have a 14 as the smallest rear sprocket. 48/14 with 26 inch wheels gives an 89 inch top gear, which is pretty pitiful for pavement use.
I was addressing mainly the concept that one can't just go faster with a higher gear, which is more important that just handing someone a solution that does not provide the desired result. As for 89 being pitiful, back in the days when triples were hard to find I set up my Moto Grand Jubilee for touring with a 38/48 and a 16-28 freewheel - high gear of 81 inches. Did not really slow me down enough to bother me. It is accurate to say that not many can spin out even an 89 inch gear. According to my bamboo slide rule an 89 in gear at 140 rpm is 37 mph. Even 120 rpm is 32 mph.