in message <[email hidden]>, David Waters
(') said:What is a compact and what are the
advantages/disadvantages?
Long ago, bicycles were made of steel and tubes were
generally of small diameter. Because the seat post was of
steel and of small diameter if you exposed a lot of it it
would flex. So frames were designed with horizontal top
tubes, in order to reduce the length of the exposed seat
tubes. The range of practical adjustment was quite small, so
many sizes had to be made and stocked, meaning that
manufacturers had quite a lot of capital tied up in stock.
Nowadays bicycles are often made of aluminium, with larger
diameter tubes. So the seat post can be of larger diameter
and hence stiffer. So you can expose more of it without
excessive flex. So you can make bikes with sloping top tubes
which give a lot more adjustment. So you don't have to make
so many sizes. These bikes with sloping top tubes and yards
of exposed seat post are called 'compacts'.
Two benefits: the manufacturers save money, so the bike may
cost less. And in an unplanned dismount you're less likely
to come down hard on the bar with your wedding tackle.
--
[email hidden] (Simon Brooke)
jasmine.org.uk~simonOpen ↗
I shall continue to be an impossible person so long
as those who are now possible remain possible --
Michael Bakunin