Originally Posted by blickblocks
I'm kind of confused by what you're saying Sheldon.
As I've understood it, since you're geared too high when starting from a standstill, the force of your pedalling is more than it should, so your chain is pulling harder. When you can spin on a geared bike instead of mash, you're trading an amount of force for an amount of chain pull. The chain isn't pulling as hard since it's moving faster.
Might be correct if there weren't such a thing as hills. Track riders don't need to deal with hills, that's the main reason they don't have gears.
A heavy tourist on a loaded bike climbing a steep hill puts WAY more stress on the chain than any track rider ever does on the boards.
I think you may be confusing force and work. Work is force times distance. If you lug a 52 tooth chainring at 50 RPM, or spin a 26 tooth at 100 RPM the same amount of work is getting done every second. The rider with the 26 who is spinning twice as fast, is only pushing half as hard on the pedals. The chain can't tell the difference.
However, if the bike is going slow enough that the rider with the 26 is able to lean his/her full weight on the pedal, the pull on the chain will be twice as high.
Sheldon "Physics" Brown