Originally Posted by 11.4
At Elite or World Cup levels, most track racers when queried will tell you that there's a difference in the responsiveness between these equivalent-geared cog and chainring combinations. It's not necessarily an obvious issue, but some riders will ride like a 54x18 in training to get an 81 inch gear, simply because they want to keep the feel of the 54 for when they're riding a 54x15 in the pursuit. I hear it too much not to believe it, and from my own experience I definitely turn in slightly faster 200 meter times on a smaller chainring than on a bigger one (compensating in the cog teeth, of course)...
I suspect the difference is that a larger chainring will flex more under load than a smaller one. For ordinary mortals this isn't much of an issue, but for elite riders it well may be. It strikes me that improved chainring rigidity is the main reason to ride 1/8" equipment rather than 3/32"