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seat post too long

Old 07-09-13, 08:13 AM
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goldfinch
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seat post too long

I just bought a new aluminum setback seat post. It is too long by a quarter of an inch or so. Can I just hack saw it off?

Kind of a stupid question but I don't want to screw it up.
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Old 07-09-13, 08:22 AM
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Hacksaw or pipe cutter.

Make sure you file the edges when done, whichever you do.

I've done it myself with a hacksaw...it's plenty easy.
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Old 07-09-13, 08:47 AM
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Hack is the tool of choice, since it doesn't raise a large outside burr.

Leave as much as possible in the frame, or at least 3" or so.
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Old 07-09-13, 08:55 AM
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It's pretty well covered here, but yes, you can just hack saw it off. However, it's still important that you leave a few inches to go into the seat tube, so only cut what you have to. Also, make sure you file down the rough edges that the saw creates, otherwise it's going to scratch up the inside of the tube and do some damage, or at least make the fit a bit wonky.
There shouldn't be much to worry about on an alumin(i)um tube.
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Old 07-09-13, 09:00 AM
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So, you hit the inside end of a water bottle boss in the seat tube?

.. thats usually the 1st obstruction..


maybe end of where the seat tube reaming was done,

so a bit smaller, inside, from there..

Last edited by fietsbob; 07-09-13 at 09:04 AM.
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Old 07-11-13, 07:01 PM
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Yeah, hit the water bottle boss. I did as you folks said and filed it off afterwards. I only took a half an inch. Now it is perfect. Thanks as always. It was surprisingly difficult to saw the tube, even when in the vice. It took a long time and I didn't get it perfectly square.
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Old 07-11-13, 07:12 PM
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Originally Posted by goldfinch View Post
Yeah, hit the water bottle boss. I did as you folks said and filed it off afterwards. I only took a half an inch. Now it is perfect. Thanks as always. It was surprisingly difficult to saw the tube, even when in the vice. It took a long time and I didn't get it perfectly square.
Squareness doesn't matter, since the end doesn't show or do anything. OTOH, if you had trouble sawing an aluminum seatpost you need a new hacksaw blade. Even the hardest aluminum post should saw like butter.
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Old 07-11-13, 07:15 PM
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Husband's hacksaw. I was suspicious that the blade was extremely dull.
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Old 07-11-13, 07:20 PM
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Originally Posted by goldfinch View Post
Husband's hacksaw. I was suspicious that the blade was extremely dull.
He must have used it to shave his legs.
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Old 07-12-13, 02:07 AM
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You need a saw blade and a ruler
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Old 07-12-13, 02:21 AM
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Originally Posted by AidanEdward View Post
You need a saw blade and a ruler
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Old 07-12-13, 07:41 PM
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Just to add one more thing that I do - Before cutting, I measure from the end of the post to the minimum insertion line. After cutting, I make a mark on the seat post the same distance from the new end. The old minimum insertion line will be too "shallow". Just to remind myself in the future, or for anyone who might buy the bike in the future.
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