Originally Posted by alanbikehouston

A cyclist who rides for fitness, and recreation, or to commute to work or school, does 90% of his riding in the 45 gear inch to 85 gear inch range. There is absolutely no valid reason for such cyclists to EVER be riding in the 90 inch to 120 inch range (the range that the top 300 or 400 pros might use for a short time trial).

On the typical 2007 model road bike with a "triple" crank, the "middle" ring provides the best and straightest chainline when you are riding in the 65 gear inch to 85 gear inch range. So, the "middle" ring is exactly where 90% of cyclists ought to be, about 90% of the time.

I was looking at a 2006 Campy drivetrain that was set up for 46 to 96 gear inches on the "small" ring and for 61 to 128 gear inches on the "big" ring. Thirty years ago, there were guys riding in the Tour de France that were not using gears over 96 inches on their "everyday" bike...time trial bikes are a different matter.

Those gears, from above 96 gear inches gear inches to 128 gear inches are sold as a marketing device, because the marketing guys understand that 40 year old accountants want the same gears that Lance Armstrong has, even though these gears are gonna tear up their knees.

Thirty years ago, road bikes were NOT just cheaper imitations of pro race bikes. They were bikes carefully designed for the needs of their owners, who were students, school teachers, bankers. The small ring was set up to provide a good chainline for the gears from around 35 gear inches to 75 gear inches. The big ring was set up to provide a good chainline from around 55 gear inches to 95 gear inches. Every gear on a bike was truly useful for an "average" cyclist, without the risk of knee damage.

But, when the marketing guys at bike companies found out how DUMB most potential customers were, the road bike got converted from being a useful bike into being a cheesy imitation of a pro racing bike. Good-bye useful "big" ring.