Seatpost sizing
01-27-07, 12:12 PM
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Seatpost sizing
I want to replace the stovepipe seatpost on my wife's mid-90's Giant Innova Hybrid with a micro-adjust post to help her dial in more comfort. The old post is worn and either says 26.6 or 26.8. My best guess is that it says 26.6, but would this be right? I know some Schwins used 26.6, but 26.8 seems like the more common. Any thoughts on what size was probably spec'd on a mid-90s Giant hybrid?
I did buy a 26.6 post which seems to go in snug (took lots of grease and twisting, appears to fit well). So, my other question is how much difference .2mm would make? I mean, if it actually should use a 26.8 and I use the 26.6 in it would this be OK if there's no play and it seems snug?
I did buy a 26.6 post which seems to go in snug (took lots of grease and twisting, appears to fit well). So, my other question is how much difference .2mm would make? I mean, if it actually should use a 26.8 and I use the 26.6 in it would this be OK if there's no play and it seems snug?
01-27-07, 12:42 PM
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If it took grease and lots of twisting, I would say stick with it.
.2mm is only going to make it harder to get in, if not impossible.
-ray
.2mm is only going to make it harder to get in, if not impossible.
-ray
01-27-07, 10:49 PM
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That .2 mm is the difference between either not fitting in at all or being loose enough that the post wont snug up right or will cause damage to the frame. Just dont do what some morons do and use a BFH and pound it in!!
01-28-07, 02:19 AM
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can you use vaseline to get a seatpost in? once the tube is all degreased and everything?
01-28-07, 05:19 AM
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Sometimes 1 measurement is worth 1,000 guesses.
1. Wrap a piece of paper around your old seatpost. Mark where it overlaps.
2. Measure the distance you just marked carefully with a millimeter measure.
3. Divide by 3.14. That's your seatpost size.
1. Wrap a piece of paper around your old seatpost. Mark where it overlaps.
2. Measure the distance you just marked carefully with a millimeter measure.
3. Divide by 3.14. That's your seatpost size.
01-28-07, 08:59 AM
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0.2 mm means everything. I remember a thread about this very subject, where the seatpost in question was 27.2 and the dude wanted to fit it into 27 mm seat tube. Well, it's impossible. And I could confirm it, as one of my MTBs uses 27 mm seatposts, and NONE of my 27.2 would fit. Yeah, 0.2 mm is a *****.
By the way, even the cheapest calipers should measure that difference (26.6 vs. 26.8).
By the way, even the cheapest calipers should measure that difference (26.6 vs. 26.8).
01-28-07, 09:05 AM
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Originally Posted by mycoatl
I did buy a 26.6 post which seems to go in snug (took lots of grease and twisting, appears to fit well). ....... would this be OK if there's no play and it seems snug?
