"bent_sprocket" <
[email protected]> wrote in message
news:[email protected]...
> what's the best way to measure my seat tube so that i can get the correct seat post size?
>
> i know that the LBS has some cone-shaped thing, but my LBS isn't that local and i'd like to order
> the correct size post for my almost done fixie.
Seat tube ID are notoriously difficult to measure with a caliper due to out-of-roundness and
the fact that that oval variance can easily be greater than the difference from one size to the
next (0.2mm).
Ideally, you should find the actual specification and clean the bore with a parallel-blade
adjustable reamer ( referenced by the mysteriously anonymous "ant" here recently).
Failing that, another effective method is to slip in seatposts until one is found which slides
neatly with full contact and then confirm that by tryng the next larger size which should start with
difficulty but be obviously too tight.
On a beaten-up seat cluster, slipping a slightly smaller post in about 30mm and pressing toward the
back of the bicycle will usually cure dented/crushed seat binder problems. You end up with little
contact in the first inch or so until the bolt is tightened, so you don't gouge up the new post with
the mangled edge near the slit.
--
Andrew Muzi
http://www.yellowjersey.org Open every day since 1 April 1971