Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 08-26-08, 08:40 PM   #1
John1992
Senior Member
Thread Starter
 
John1992's Avatar
 
Join Date: Aug 2006
Location: Toronto Canada
Bikes: Surly Cross Check
Posts: 298
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Extra Long Seat Post

Hi,
I bought a inexpensive bike to comute to work with. I am rather tall (6.6) and I think the bike I bought is just not large enough. I am comfortable except for the seat not being high enough. I went to my LBS that they sold me a seat post that was a bit higher and they told me it was the highest that they carry. Sorry I do not have the measurements handly.

Anyway, do you know any place where I can get extra long seat posts, are there any pitfalls I need to be aware of and is there any danger of having them too long? I have seen some folding bikes with what look like 2 ft long seat posts so I am thinking that might be a good route to take.

Thanks for your help
John1992 is offline   Reply With Quote
Old 08-26-08, 09:20 PM   #2
z415
Senior Member
 
z415's Avatar
 
Join Date: Apr 2006
Location: Gainesville/Tampa, FL
Bikes: Trek 1000, two mtbs and working on a fixie for commuting.
Posts: 2,343
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Lower back pain unless you raise your bars too.
z415 is offline   Reply With Quote
Old 08-27-08, 09:54 AM   #3
CACycling
Senior Member
 
CACycling's Avatar
 
Join Date: Feb 2008
Location: Oxnard, CA
Bikes: '08 Fuji Roubaix RC; '07 Schwinn Le Tour GS; '92 Diamond Back Ascent EX
Posts: 4,565
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
^^^+1^^^
You can get seat posts in most diameters up to 350mm long. Find out what diameter your post is (usually marked on the post below the minimum insertion line) and Google "seat post ??.?" (replace the ??.? with your seat post diameter) and also check on eBay. Depending on diameter, you might get one even longer. As noted above, you probably won't be comfortable unless you raise your bars and, after that, you'll probably find the reach too short to be really comfortable. Bottom line, there is reason bikes are sold in a lot of different sizes.
CACycling is offline   Reply With Quote
Old 08-27-08, 02:52 PM   #4
Mondoman
Senior Member
 
Join Date: Apr 2008
Location: A Latvian in Seattle
Bikes:
Posts: 1,020
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
As alluded to above, be sure not to raise your seatpost up so high that the minimum insertion line is visible! That marks the minimum amount of tube that needs to be inside the frame to provide the mechanical support for the seat and you. The line is often a set of stamped markings such as ">>>>>>>>>>>>>>>>>>> <<<<<<<<<<<<<<<<" around the tube.
Mondoman is offline   Reply With Quote
Old 08-27-08, 03:03 PM   #5
cascade168
Klaatu barada nikto
 
cascade168's Avatar
 
Join Date: Sep 2004
Location: Southern NH
Bikes:
Posts: 1,453
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Seatposts of 400mm, and more, can be ordered through any shop. Kalloy makes a 400 and Thomson makes a 410, as a couple of examples.
cascade168 is offline   Reply With Quote
Old 08-27-08, 05:21 PM   #6
G piny parnas
messenger
 
Join Date: Aug 2008
Location: WLA
Bikes: pinarellos and a colnago
Posts: 599
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
if you are a bit of a bouncy rider-- I am not willing to raise the post above cheaper man. specs--- you must spread the stress -- so to speak--- posts break and lousy stems snap.
G piny parnas is offline   Reply With Quote
Old 08-06-14, 12:50 PM   #7
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
???
I'm also looking for a longer seatpost than what I now have.
The standard Dahon folding bike (Speed 7) has a seatpost measuring 580mm. (I have one.)
The Neo Volt Sport electric folding bike also has a seatpost measuring 580mm. (I have one.)
Not sure why the belief that 400mm or so is the longest. Longer for a typical folding bike would be over 580mm.
kawika808 is offline   Reply With Quote
Old 08-06-14, 12:53 PM   #8
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 18,913
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 236 Post(s)
I bought a Chromoly 1" seatpost under the Red Line Brand. long strong and modestly priced ..

frame larger seat tube bore ? sizing shims make up the difference..
fietsbob is offline   Reply With Quote
Old 08-06-14, 12:54 PM   #9
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'm also looking and it's 2014!
For anyone else who comes across this: a good idea is to ensure strength--you don't want to have the post buckle under you. One solution is to find a wooden dowel the right diameter (you'll have to do some planing or power sanding to get the curves out, and taper the top end so it goes in farther) and pound it up into the post. To be sure it doesn't fall out, drill a small hole through the post and into the dowel and insert a long, thin screw or nail

This doesn't add a lot of weight and it's well worth it for the safety factor. This has enabled me to raise the post above the max and still be OK. But I'd rather find a longer post.
kawika808 is offline   Reply With Quote
Old 08-06-14, 01:11 PM   #10
AnkleWork
Senior Member
 
Join Date: Jan 2013
Location: High Plains
Bikes: old clunker
Posts: 1,963
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Quote:
Originally Posted by kawika808 View Post
I'm also looking and it's 2014! . . .
Really?! Are you sure it's not 2008?
AnkleWork is offline   Reply With Quote
Old 08-06-14, 01:58 PM   #11
ksisler
Senior Member
 
Join Date: Sep 2012
Bikes:
Posts: 1,647
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Seriously though, a quick look on Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more finds extra long alum seatpost in the $10 range that are plenty strong.
ksisler is offline   Reply With Quote
Old 08-06-14, 02:21 PM   #12
gsa103
Senior Member
 
Join Date: May 2013
Location: SF Bay Area
Bikes: Bianchi Infinito (Celeste, of course)
Posts: 2,823
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 66 Post(s)
Quote:
Originally Posted by kawika808 View Post
This doesn't add a lot of weight and it's well worth it for the safety factor. This has enabled me to raise the post above the max and still be OK. But I'd rather find a longer post.
No, it's helped you convince yourself that you're ok. The minimum seat post insertion is also related to frame construction. What can happen is that instead of the seatpost failing, the frame fails because the seatpost isn't inserted far enough.
gsa103 is offline   Reply With Quote
Old 08-06-14, 02:22 PM   #13
Wilfred Laurier
Seņor Member
 
Wilfred Laurier's Avatar
 
Join Date: Feb 2013
Bikes:
Posts: 3,713
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 27 Post(s)
Quote:
Originally Posted by ksisler View Post
Seriously though, a quick look on Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more finds extra long alum seatpost in the $10 range that are plenty strong.
it is difficult though
to use amazon to buy the op a seatpost
in 2008
unless they also sell time machines
Wilfred Laurier is offline   Reply With Quote
Old 08-06-14, 02:39 PM   #14
cranky old road
Let your bike be the tool
 
cranky old road's Avatar
 
Join Date: Jun 2006
Location: NC/SC border
Bikes: '66 Raleigh Carlton, '70 Ron Cooper, '95 Bianchi CD'I, Zonal Frame with Xenon gruppo, Carbon Frame with Record Gruppo, Columbia Twosome, Terry Classic, Bianchi SX, Gravity SS/FG
Posts: 820
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by kawika808 View Post
I'm also looking and it's 2014!
For anyone else who comes across this: a good idea is to ensure strength--you don't want to have the post buckle under you. One solution is to find a wooden dowel the right diameter (you'll have to do some planing or power sanding to get the curves out, and taper the top end so it goes in farther) and pound it up into the post. To be sure it doesn't fall out, drill a small hole through the post and into the dowel and insert a long, thin screw or nail

This doesn't add a lot of weight and it's well worth it for the safety factor. This has enabled me to raise the post above the max and still be OK. But I'd rather find a longer post.
A potential problem with raising the post above the max is damage to the frame as there will be increased leverage working against a shorter insertion area in the frame.
cranky old road is offline   Reply With Quote
Old 08-06-14, 02:44 PM   #15
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Apparently it also convinced my bike, since I have ridden about 25 miles a week for several years, half of those miles with the additional load and stress (including oscillation every time a bump is encountered) of a 10' surfboard on a Carver rack suspended from the seat post and no deformation or cracks including the frame. The power of suggestion is indeed strong.
kawika808 is offline   Reply With Quote
Old 08-06-14, 02:46 PM   #16
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Wilfred Laurier View Post
it is difficult though
to use amazon to buy the op a seatpost
in 2008
unless they also sell time machines
Could be, but so what? Snotty remarks solve nothing. I came across this thread this year, and so did you. So guess what: the thread is still relevant. Even though your remarks aren't.
kawika808 is offline   Reply With Quote
Old 08-06-14, 02:47 PM   #17
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by AnkleWork View Post
Really?! Are you sure it's not 2008?
Grow up or tune out.
kawika808 is offline   Reply With Quote
Old 08-06-14, 02:48 PM   #18
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by gsa103 View Post
No, it's helped you convince yourself that you're ok. The minimum seat post insertion is also related to frame construction. What can happen is that instead of the seatpost failing, the frame fails because the seatpost isn't inserted far enough.
Apparently it also convinced my bike, since I have ridden about 25 miles a week for several years, half of those miles with the additional load and stress (including oscillation every time a bump is encountered) of a 10' surfboard on a Carver rack suspended from the seat post and no deformation or cracks including the frame. The power of suggestion is indeed strong.
kawika808 is offline   Reply With Quote
Old 08-06-14, 02:50 PM   #19
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by cranky old road View Post
A potential problem with raising the post above the max is damage to the frame as there will be increased leverage working against a shorter insertion area in the frame.
Good point, and I wouldn't do this if I were going to indulge in off-road riding. But on decent city streets it has worked out well for me. I have ridden about 25 miles a week for several years, half of those miles with the additional load and stress (including oscillation every time a bump is encountered) of a 10' surfboard on a Carver rack suspended from the seat post and no deformation or cracks including the frame. The bike is a Dahon Speed 7.
kawika808 is offline   Reply With Quote
Old 08-06-14, 04:15 PM   #20
JohnDThompson 
Old fart
 
JohnDThompson's Avatar
 
Join Date: Nov 2004
Location: Appleton WI
Bikes: Several, mostly not name brands.
Posts: 16,374
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 64 Post(s)
Quote:
Originally Posted by cranky old road View Post
A potential problem with raising the post above the max is damage to the frame as there will be increased leverage working against a shorter insertion area in the frame.
Indeed. And then you risk ruining the frame like this:



Seat tube crack: braze-fill vs tube replacement
JohnDThompson is offline   Reply With Quote
Old 08-06-14, 06:55 PM   #21
ksisler
Senior Member
 
Join Date: Sep 2012
Bikes:
Posts: 1,647
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by Wilfred Laurier View Post
it is difficult though to use amazon to buy the op a seatpost
in 2008 unless they also sell time machines
Wilfred; Apparently they do sell time machines... < ROFLOL>

Amazon.com: Big Bang Theory [HD]: Season 1, Episode 14 "The Nerdvana Annihilation [HD]": Amazon Instant Video

Apologies for having fun at your expense...

/K
ksisler is offline   Reply With Quote
Old 08-07-14, 05:04 AM   #22
Dan Burkhart 
Senior member
 
Dan Burkhart's Avatar
 
Join Date: Oct 2004
Location: Oakville Ontario
Bikes:
Posts: 5,927
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Quote:
Originally Posted by kawika808 View Post
???
I'm also looking for a longer seatpost than what I now have.
The standard Dahon folding bike (Speed 7) has a seatpost measuring 580mm. (I have one.)
The Neo Volt Sport electric folding bike also has a seatpost measuring 580mm. (I have one.)
Not sure why the belief that 400mm or so is the longest. Longer for a typical folding bike would be over 580mm.
A typical folding bike post is also much larger in diameter than a typical DF post.Good luck finding a 27.2 post in 580mm.
Dan Burkhart is offline   Reply With Quote
Old 08-07-14, 08:12 AM   #23
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Dan Burkhart View Post
A typical folding bike post is also much larger in diameter than a typical DF post.Good luck finding a 27.2 post in 580mm.
Right. But neither the OP nor I ever mentioned 27.2. So I won't be needing either the "good luck" to find what I'm not looking for, nor the sarcasm.
kawika808 is offline   Reply With Quote
Old 08-07-14, 08:23 AM   #24
kawika808
Junior Member
 
Join Date: Jul 2014
Bikes:
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by JohnDThompson View Post
Indeed. And then you risk ruining the frame like this:

Seat tube crack: braze-fill vs tube replacement
The issue of frame damage is certainly real. But there are other factors.

Which is worse: having a post that is, say 1-2 inches longer than standard spec, or a bike at standard spec ridden by someone who weighs 220 pounds, or ridden by someone who hits a lot of large bumps/holes and does not use the legs as shock absorbers?

I leave it to someone else to work out the precise math, but using a bike only on paved surfaces (as I do), avoiding bumps as much as possible (which I do), standing on the pedals to remove weight from the seat if a bump is encountered (which I do), and being of a reasonable body weight (which I am) results in less stress on the post and the bike than someone who uses a normal post at normal height and does none of the above.

Last edited by kawika808; 08-07-14 at 08:23 AM. Reason: Program error
kawika808 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 03:45 AM.