Advertise on Bikeforums.net



User Tag List

Results 1 to 10 of 10
  1. #1
    Junior Member
    Join Date
    Jun 2004
    Location
    Southern New Jersey
    Posts
    16
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Seat post won't cooperate

    This season I've had this nagging problem with my seat post. It seems no matter how tight I make the collar, the seat post slides down during my ride. Last night I even de-biked during my ride (at about the 10 mile mark) to raise the post and by the end of the ride (25 miles) it found it's way down again. Any helpful suggestions? Thanks in advance.

  2. #2
    Senior Member matimeo's Avatar
    Join Date
    Feb 2006
    Location
    Beaverton, OR
    My Bikes
    Windsor Cyclo, Nishiki Seral
    Posts
    634
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    1. your seat post is too small for the bike
    2. the bolt that connects the collar is too long (can't screw far enough and so it is loose).
    I can't think of what else it could be. The solution to #1 is obvious, if it is #2 then you can either get a longer bolt or you can put a shim or washer on the bolt- on the outside of the collar- and that will effectually lengthen the bolt and make it clamp tighter.

  3. #3
    Lost in the Black Hills mx_599's Avatar
    Join Date
    May 2005
    Posts
    5,725
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by ron m View Post
    This season I've had this nagging problem with my seat post. It seems no matter how tight I make the collar, the seat post slides down during my ride. Last night I even de-biked during my ride (at about the 10 mile mark) to raise the post and by the end of the ride (25 miles) it found it's way down again. Any helpful suggestions? Thanks in advance.
    no, i don't believe it is what was mentioned above...don't get me wrong, they are viable answers.

    i had the same issues with my seat post and similar issues with my front derailleur. i am FAR from an incompetent mechanic...so i know it is not my fault.

    for my thomson post into a steel frame i used some permatex gasket sealing glue that never really dries but gets sort of tacky. that helped for many months. however, the other day it actually slipped after i made an adjustment to the height. i guess i broke the "bond".

    next on my list to try if it gives me any more probs is something like a little 3M tacky spray "glue" stuff. or possibly a weak thread locking agent (but i don't think this would "set" up...not sure)

    anyhow, just know you're not alone.

    as far as my FD goes, i have to use these stupid plastic spacers which seems like they are Teflon impregnated

    i've had continual problems with the FD and it is not really my fault. i've done nothing wrong or incorrectly. incredibly annoying...

  4. #4
    Last one to the top... Little Darwin's Avatar
    Join Date
    Jul 2005
    Location
    Wilkes-Barre, PA
    My Bikes
    Many
    Posts
    6,845
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Some bikes come with shims for the seat post. If so, make sure that the slot in the shim is lines up with the slot in your seat tube. This caused me some headaches on my bike before I discovered it. I didn't even know I had a shim before I discovered this issue on mine. Mine apparently got twisted while making height or position adjustments at some point.

    These others are just to make sure you've checked the obvious...

    From what you have written, I assume you have tightened the nut up a half turn or so before clamping it down... (if you have a quick release)

    Also, is the opening of your clamp aligned with the slot in your seat tube? It should be...
    Slow Ride Cyclists of NEPA

    People do not seem to realize that their opinion of the world is also a confession of character.
    - Ralph Waldo Emerson

  5. #5
    Senior Member capwater's Avatar
    Join Date
    Dec 2004
    Location
    Quahog, RI
    My Bikes
    Giant TCR Comps, Cdale R5000, Klein Q-Pro, Litespeed Siena, Piasano 105, Redline Conquest Pro, Voodoo Bizango, Fuji Aloha
    Posts
    1,509
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    That is often a problem with carbon posts in carbon frames (you haven't indicated the material). A little roughing up the post (below the insertion level) with some fine grit sandpaper will solve the slippage.

  6. #6
    Junior Member
    Join Date
    Jun 2004
    Location
    Southern New Jersey
    Posts
    16
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    More information

    Sorry for the incomplete post. I ride a 2002 Lemond Buenos Aires, steel frame with a carbon seat post, stock. The fastener isn't a quick release and requires an Allen wrench to tighten. Thanks for all the suggestions. I'll report back tomorrow.

  7. #7
    The Cycling Photographer SipperPhoto's Avatar
    Join Date
    Jun 2002
    Location
    Orange, CA
    Posts
    1,411
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by ron m View Post
    Sorry for the incomplete post. I ride a 2002 Lemond Buenos Aires, steel frame with a carbon seat post, stock. The fastener isn't a quick release and requires an Allen wrench to tighten. Thanks for all the suggestions. I'll report back tomorrow.
    I'm having the same problem with my Steelman, and an Easton Carbon seatpost. Already snapped a seat collar bolt, after tightening it, and then trying to loosen it to take it out... I've decided to just switch out to an aluminum seatpost, it frustrated me that much... I never seem to have a problem with those!
    Jeff

    Check out TorelliFan.com! Submit your bike, tell us about an epic ride, or just come to check out the eye candy!

  8. #8
    Extra Medium Member redtires's Avatar
    Join Date
    Jul 2006
    Location
    Louisville, Co
    My Bikes
    Fuji Roubaix 1.0 (Sampson Kalispell Ti GONE); VooDoo Wanga (Specialized Stumpy: GONE)
    Posts
    1,582
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    This bike uses a seat collar, yes? I'm guessing that it is not a brazed on seat clamp, as many builders don't use these anymore, other than custom builders. I suppose you could try a new clamp, it's possible that the old one is stretched. And don't use grease on a carbon post. There should be no chance of a corrosive reaction like steel against aluminum.

  9. #9
    Senior Member
    Join Date
    Jun 2005
    Posts
    776
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    ron m,

    You might find something here....................

    http://www.loosescrews.com/index.cgi...d=593620920616


    Good luck.

  10. #10
    SOS
    SOS is offline
    Member
    Join Date
    Apr 2007
    Posts
    36
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I had this issue for a long time - 0.5mm to 1mm of slippage every km! Carbon post, alu frame. Clyde, 300 lbs.

    Tightening it did not do much. At one point, I noticed the edge of the slot in the frame had worn a groove in my seatpost! I sanded it smooth (only the upper decorative layer was damaged - I caught it in time), added a soda can shim (due to the sanding making the post smaller) and bought a new clamp (bolt, instead of my old quickrelease), which I tightened down REAL right. As in 3-4 turns beyond "dangeous-seeming tight".

    It still slipped!

    However, the soda can shim sort of crumpled due to the slippage and this caused enough of an obstruction to stop it from slipping after a cm. I find the height pretty comfortable, so I am not going to mess with it anymore until it becomes a problem again

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •