[net.bicycle] Vertical dropouts

msw@drux1.UUCP (Mike Walpole) (05/13/85)

>  For some reason I recall only seeing track bikes with vertical
>  dropouts. Does this seem right?


Track bikes have paralell dropouts.  This is to accomadate alot of 
chain adjustment when changing the gearing without having to change
the chain length.  A track bike chain has to be very snug because
it is a fixed gear bike. (ie. no brakes no coasting)  Vertical dropouts
are seen on some racing bikes.  The main reason is to speed wheel changes.
It is also done because some times on a racing frame the rear geometry
is so tight that normal dropouts would not allow removal of the rear
wheel. (Look at a Cannondale sometime.)  There are some problems with
verticals.  One is that its easier for the rear wheel to fall out if
the quick release is not tight.  The other is that if the frame gets
bent there is no way to align the rear wheel in the chainstays.

Also Track bikes don't have quick releases.  They use solid axles and
axle nuts. (Who wants to have an axle break sprinting at 40+ mph ?)

Mike Walpole