Shortening a seat tube

In article <[email hidden]>, Robert Strickland

Quoted message said:

I've got a frame I'm about to get repainted but I was wondering if there would be any reason why I
shouldn't have the seat tube 'adjusted' at the same time. The problem is that there is a good 4 cm
of seat tube above the top tube. This means that to get a good fistful of seat post to protrude
above the seat tube, the saddle ends up being a cm or two higher than it needs to be. This would be
no big deal except that I think I would be a lot more comfortable sitting a cm or two lower as well
as being a little closer to the bars. Are there any structural reasons why I couldn't just have a
frame builder take 2 cm off the tube before I get it repainted?

Assuming the bike is out of warranty and a qualified person does the work, there is no problem
with doing this. They can shorten the seat tube, cut a slot in it, and you can use an aluminum
clamp to fix the seatpost in place. Some bikes come that way from the manufacturer, it is
sometimes done as a cost-saving measure since a TIG-welded bike can be produced more cheaply
without the integrated binder.

--Paul

"Robert Strickland" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I've got a frame I'm about to get repainted but I was wondering if there would be any reason why I
shouldn't have the seat tube 'adjusted' at the same time. The problem is that there is a good 4 cm
of seat tube above

the

Quoted message said:

top tube. This means that to get a good fistful of seat post to protrude above the seat tube, the
saddle ends up being a cm or two higher than it needs to be.

Why do you need to have a "fistful" of seatpost showing? Just set the seat height the proper height
for you and forget about the fact that some of it is covered by the seat tube collar.

Quoted message said:

This would be no big deal except that I think I would be a lot more comfortable sitting a cm or
two lower as well as being a little

closer

Quoted message said:

to the bars. Are there any structural reasons why I couldn't just have a frame builder take 2 cm
off the tube before I get it repainted?

Thanks in advance, Rob Strickland

"Robert Strickland" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

I've got a frame I'm about to get repainted but I was wondering if there would be any reason why I
shouldn't have the seat tube 'adjusted' at the same time. The problem is that there is a good 4 cm
of seat tube above the top tube. This means that to get a good fistful of seat post to protrude
above the seat tube, the saddle ends up being a cm or two higher than it needs to be.

Why does there need to be a "good fistful" of seatpost protruding, other than a perhaps cosmetic
one? Couldn't you just lower the saddle one or two cm and be done with it? If anything, you could
actually have the bike be lighter; since the seat tube extends up so far, you can cut off excess
seatpost length that would be inside the tube, and not serving any structural purpose.

"Robert Strickland" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I've got a frame I'm about to get repainted but I was wondering if there would be any reason why I
shouldn't have the seat tube 'adjusted' at the same time. The problem is that there is a good 4 cm
of seat tube above the top tube. This means that to get a good fistful of seat post to protrude
above the seat tube, the saddle ends up being a cm or two higher than it needs to be. This would
be no big deal except that I think I would be a

lot

Quoted message said:

more comfortable sitting a cm or two lower as well as being a little

closer

Quoted message said:

to the bars. Are there any structural reasons why I couldn't just have a frame builder take 2 cm
off the tube before I get it repainted?

Without knowing what frame it is, it probably could be trimmed, especially if it is steel. You
should consult with a frame repair shop to see if there are any mitigating factors.

But I see this as an aesthetic issue. You won't change your riding position by trimming the
seat tube.

Unless. . . Are you saying that you have your saddle higher than it should be because it cannot go
low enough into the frame? That wouuld seem to indicate a frame that's overly large for you.

When you say "closer to the bars" do you mean because lowering the saddle along a 74-degree
line moves it forward? That small effect is lost in the noise of your saddle's fore-aft
adjustment on the post.

Do write again, perhaps with a photo link. It would seem that a fitting session is in order before
the paint job.

--
Andrew Muzi yellowjersey.orgyellowjersey.orgOpen ↗ Open every day since 1 April 1971

"Robert Strickland" <[email hidden]> wrote in message
news:<[email hidden]>...

Quoted message said:

I've got a frame I'm about to get repainted but I was wondering if there would be any reason why I
shouldn't have the seat tube 'adjusted' at the same time. The problem is that there is a good 4 cm
of seat tube above the top tube. This means that to get a good fistful of seat post to protrude
above the seat tube, the saddle ends up being a cm or two higher than it needs to be.

Sir, If you are worried about having a fistful of seatpost, why not just count a fistful of
seapost/extended seat tube and call it good? Said fist is a sizing convention, no? Unless there is
some unexplained virtue to having the ACTUAL aluminum seatpost showing the width of your hand, why
hack up your frame? Brian Plaugher

Quoted message said:

Without knowing what frame it is, it probably could be trimmed, especially if it is steel. You
should consult with a frame repair shop to see if

there

Quoted message said:

are any mitigating factors.

But I see this as an aesthetic issue. You won't change your riding

position

Quoted message said:

by trimming the seat tube.

Unless. . . Are you saying that you have your saddle higher than it should be because it cannot go
low enough into the frame? That wouuld seem to indicate a frame that's overly large for you.

When you say "closer to the bars" do you mean because lowering the saddle along a 74-degree line
moves it forward? That small effect is lost in the noise of your saddle's fore-aft adjustment on
the post.

Do write again, perhaps with a photo link. It would seem that a fitting session is in order before
the paint job.

--
Andrew Muzi yellowjersey.orgyellowjersey.orgOpen ↗ Open every day since 1 April 1971

Thanks for the comments Andrew (and others who've commented). The frame is steel and the main issue
is fit but I think the frame is only marginally too big. I've been riding on this frame for a couple
of years and I am able to get reasonably comfortable on it but only if I lower the seat post to just
1 or 2 cm above the seat tube. For some time I've felt a little bit stretched, especially on long
rides so I swapped out the original stem for one that brings the bars closer by about 1 1/2 cm. That
seemed to help a lot. I also swapped the seatpost out for one that isn't set back quite as far but I
haven't had a chance to really experiment with that yet. My main interest in shortening the seat
tube is to give myself just a little bit more room to play with. The second issue is that with the
seat post so low it's virtually impossible to affix things like saddlebags or u-lock brackets to the
post, which I'd like to be able to do. Since the tube projects at least 2 cm higher above the top
tube than any other frame I've owned it seemed like it shouldn't be a problem to take a couple of
centimeters off. I've posted a couple of pics but since the frame is stripped I don't know how much
they really help.

www.invertebratadesigns.com/pics/st1.jpg www.invertebratadesigns.com/pics/st2.jpg

Thanks, Rob

In article <[email hidden]>, Robert Strickland

Quoted message said:

www.invertebratadesigns.com/pics/st1.jpg www.invertebratadesigns.com/pics/st2.jpg

Looks like you could easily reduce that exposed tubing by about half, maybe a little more. Not being
able to see you and the bike I haven't a clue if it really fits you but shortening that tube is no
big deal if that's what you want.

([email hidden]) offered:

Quoted message said:

Quoted message said:

Without knowing what frame it is, it probably could be trimmed,

especially

Quoted message said:

Quoted message said:

if it is steel. You should consult with a frame repair shop to see if

there

Quoted message said:

are any mitigating factors.

But I see this as an aesthetic issue. You won't change your riding

position

Quoted message said:

by trimming the seat tube.

Unless. . . Are you saying that you have your saddle higher than it

should

Quoted message said:

Quoted message said:

be because it cannot go low enough into the frame? That wouuld seem to indicate a frame that's
overly large for you.

When you say "closer to the bars" do you mean because lowering the

saddle

Quoted message said:

Quoted message said:

along a 74-degree line moves it forward? That small effect is lost in

the

Quoted message said:

Quoted message said:

noise of your saddle's fore-aft adjustment on the post.

Do write again, perhaps with a photo link. It would seem that a fitting session is in order
before the paint job.

"Robert Strickland" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Thanks for the comments Andrew (and others who've commented). The frame is steel and the main
issue is fit but I think the frame is only marginally

too

Quoted message said:

big. I've been riding on this frame for a couple of years and I am able to get reasonably
comfortable on it but only if I lower the seat post to just

1

Quoted message said:

or 2 cm above the seat tube. For some time I've felt a little bit

stretched,

Quoted message said:

especially on long rides so I swapped out the original stem for one that brings the bars closer by
about 1 1/2 cm. That seemed to help a lot. I

also

Quoted message said:

swapped the seatpost out for one that isn't set back quite as far but I haven't had a chance to
really experiment with that yet. My main interest

in

Quoted message said:

shortening the seat tube is to give myself just a little bit more room to play with. The second
issue is that with the seat post so low it's

virtually

Quoted message said:

impossible to affix things like saddlebags or u-lock brackets to the post, which I'd like to be
able to do. Since the tube projects at least 2 cm higher above the top tube than any other frame
I've owned it seemed like

it

Quoted message said:

shouldn't be a problem to take a couple of centimeters off. I've posted a couple of pics but since
the frame is stripped I don't know how much they really help.

www.invertebratadesigns.com/pics/st1.jpg www.invertebratadesigns.com/pics/st2.jpg

That frame can be trimmed quite a bit and a seat binder brazed on the back. There are very handy
cast "lugs" just for this sort of repair that include a binder and a ring around the top of the seat
tube. Those require minimal height over the top tube as thet are designed for use after a failure.

--
Andrew Muzi yellowjersey.orgyellowjersey.orgOpen ↗ Open every day since 1 April 1971