Seatpost Fitting
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Seatpost Fitting
I currently have a 26.6 seatpost on my road bike. I was wondering if using a 26.2 seatpost in the future will cause any problems in fitting? Will it be too small to fit in my frame leading to overtightening the lug in the back?
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If a 26.6 seatpost fits perfectly now with no play in it at all, then you need a 26.6 period. You should not play around with other size seat posts since all that will do is slowly weaken the seatpost and deform the seat post tightening ears. Your post should fit snugly with NO play.
A 26.2 post will be WAYYYY too small. You might barely get away with possibly using a 26.5 post but not sure if they even make such a thing.
A 26.2 post will be WAYYYY too small. You might barely get away with possibly using a 26.5 post but not sure if they even make such a thing.
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Assuming the current one is a good fit - yes.
Assuming the current one is a good fit - quite probably.
But you can always shim the 26.2 to something a lot closer to 26.6.
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I've been using a bronze seat post shim that is 3" long in my MTB since 1997. I'm tall and have a lot of seat post showing and for a period of several years I tipped the scales just a few ounces under 250 Lbs. I have experienced no issues using a shim.
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These threads drive me absolutely batty. Seatposts are available in basically every size ever used, and 99% of them can be had for dirt cheap.... Why not get the right size? It sounds to me like you already have the right size (if, in fact, 26.6 is the correct size for your frame)-- why not just keep that one in service?
If the current post is broken, why not just buy a danged 26.6mm post? I have like, three 26.6 mm posts in my basement, plus a few in some bikes. Common used 26.6 posts from the 80s are free or basically free when you find them. Brand new pipe-n-guts style seatposts are less than $5 (and an extra $2.50 for the guts). You might be tempted to save a few bucks by just using what's on hand, but consider this: a seatpost is a lot cheaper than a frame. Off-sized posts have killed a lot of frames over the years.
If the current post is broken, why not just buy a danged 26.6mm post? I have like, three 26.6 mm posts in my basement, plus a few in some bikes. Common used 26.6 posts from the 80s are free or basically free when you find them. Brand new pipe-n-guts style seatposts are less than $5 (and an extra $2.50 for the guts). You might be tempted to save a few bucks by just using what's on hand, but consider this: a seatpost is a lot cheaper than a frame. Off-sized posts have killed a lot of frames over the years.
#6
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More common sizes are 25.4 , or 1 inch, then you will find shims for all sorts of frame ID's
precision machined.. Wheels Mfg and QBP-PS both make seatpost sizing shims
less common 25.0, mm.. I have bought USE shims from the UK [through LBS]
they, the USE company, make seatposts just in 25 then in 27.2 , then again in larger than that
rather than all diameters in 0.2mm steps.
Kalloy makes seat posts like that they are very economical, and commonly available.
I bought a Thudbuster suspension seat post in 27.2, and a shim 27.2>31.4
to use in my frame with a 31.4 mm ID seat tube..
undersized seatposts, if used, damage frames , maybe irreversibly.
precision machined.. Wheels Mfg and QBP-PS both make seatpost sizing shims
less common 25.0, mm.. I have bought USE shims from the UK [through LBS]
they, the USE company, make seatposts just in 25 then in 27.2 , then again in larger than that
rather than all diameters in 0.2mm steps.
Kalloy makes seat posts like that they are very economical, and commonly available.
I bought a Thudbuster suspension seat post in 27.2, and a shim 27.2>31.4
to use in my frame with a 31.4 mm ID seat tube..
undersized seatposts, if used, damage frames , maybe irreversibly.
Last edited by fietsbob; 10-18-13 at 09:25 AM.
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If the 26.6 post fits and works, why would you even consider another? It's like saying I've worn size 9 shoes all my life, but I'm thinking of trying some size 7.
Post fit is very critical, and has to be a running fit inside the tube. Otherwise, even if you can clamp it at the top, it's rock and move around below, creaking and putting undue stress on the seat tube just below the clamp
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Question.
If the 26.6 post fits and works, why would you even consider another? It's like saying I've worn size 9 shoes all my life, but I'm thinking of trying some size 7.
Post fit is very critical, and has to be a running fit inside the tube. Otherwise, even if you can clamp it at the top, it's rock and move around below, creaking and putting undue stress on the seat tube just below the clamp
If the 26.6 post fits and works, why would you even consider another? It's like saying I've worn size 9 shoes all my life, but I'm thinking of trying some size 7.
Post fit is very critical, and has to be a running fit inside the tube. Otherwise, even if you can clamp it at the top, it's rock and move around below, creaking and putting undue stress on the seat tube just below the clamp
I wanted to install a fluted seat post and had a 26.2 lying around. Was wondering if I should get another one.
#9
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Math: 26.6mm - 26.2mm = 0.4mm '/, 2 = 0.2mm, you need an 0.2mm thick shim to make up the difference..
what makes the fluted seat post so special ?
its a look that has been done in cheap as well as expensive seatposts ..
what makes the fluted seat post so special ?
its a look that has been done in cheap as well as expensive seatposts ..
#10
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I had a person that came in to my shop last night asking fo a seat pole. You mean a seat post? "Yeah, seat pole." What size? "A long one." No, no, a seat post, what diameter, how thick? "Yeah, a long one, for a crusier. A pole." show him the parts binwith seat poles, eh posts. He grabes a long one, "Yeah, that's for a cruiser, How much?" 2 bucks. Pays and leaves happy.
I know it doen't help the op, but since we are talking about poles...
I know it doen't help the op, but since we are talking about poles...
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I had a person that came in to my shop last night asking fo a seat pole. You mean a seat post? "Yeah, seat pole." What size? "A long one." No, no, a seat post, what diameter, how thick? "Yeah, a long one, for a crusier. A pole." show him the parts binwith seat poles, eh posts. He grabes a long one, "Yeah, that's for a cruiser, How much?" 2 bucks. Pays and leaves happy.
I know it doen't help the op, but since we are talking about poles...
I know it doen't help the op, but since we are talking about poles...
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