Originally Posted by Sheldon Brown
This all begs the question of
why you would want super-tight clearance between the tire and the seat tube.
There is a long-held superstition that this somehow makes a bike faster or quicker handling, but I don't buy it.
Short chainstays lead to poor weight distribution and an uncomfortable ride, with no significant benefit to couteract these drawbacks.
Sheldon "Short Chainstays Are A Silly Fad" Brown
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| To see what is in front of one's nose |
| needs a constant struggle |
| --George Orwell |
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Since the force put on the hub comes from where the wheel touches the ground in a straight line through the hub, the reactant force from the seat stays to keep the hub in place is in the opposite direction (or straight down). The close the seat stay angle is to 90 degrees from the ground, the better it can do this. So the closer the rear wheel is to the seat stay, the closer the angle of the seat stay to 90 deg. and the stiffer the rear of the frame. Which means better power transfer under hard sprinting, a definite benefit for a track bike.