At 11:13 AM 1/9/07 -0500, Sheldon Brown wrote:
>Rear-opening fork ends have no virtue for well designed frames,
>they're just an atavistic styling exercise.
Sheldon is probably right. I think people just demanded these dropouts on track bikes because of the notion that you could not pull the wheel out by hard sprinting. Of course, if the axle nuts were not tightened properly, you would pull the wheel askew and quickly slow down long before pulling the wheel out. Some track ends do have adjustors to prevent slippsge, especially in Keirin racing, but it's probably a safety measure to prevent the sudden slowing mentioned from endangering other riders. Of course, the traditional roadsters from the early part of the last century that are still in use in the Third World, had gaspipe chainstays with the ends "hammered" flat with rear facing slots cut in them. These use chain adjustors because the tools at hand likely can't tighten the axle nuts sufficiently.
John Betmanis
Woodstock, Ontario
Canada