Slipping seat post - WTB Phoenix- Mtbr.com
Results 1 to 54 of 54
  1. #1
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423

    Slipping seat post - WTB Phoenix

    I'm looking for some advice/help on a slipping seat post. It has always been a problem on this bike. I've used both an American Classic, and a Thomson Elite (current), and both slip.

    The seat tube has "ears" welded to it for a quick release fastener. Initially I thought the QR might be the problem, so at some point I threaded a heli-coil into one side and use a grade 8 bolt through the other, but it still slips.

    I tighten it to the point that I'm afraid I'm either going to snap the bolt or worse. I noticed today that it's slipped again, so thought I'd ask for tips on what I could try next while it's on my mind.

    FWIW - the first post I used was an AC, the slipping wore a flat spot on the post to where it won't stay where I need it at all. The current Thomson post may be worn the same way, but I haven't checked it. I have a spare Syncros stashed away in case the Thomson gets to the point of not being usable. I know it's slipping because I've got it marked with a white line - I raise the post up to where the line is 1/4" or so above the top of the seat tube, and eventually it'll end up inside the tube and out of sight. Then wash, rinse, repeat.

    Any tips on what I could do to fix this situation is appreciated.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  2. #2
    defender of bad taste
    Reputation:
    Join Date
    Nov 2007
    Posts
    1,600
    Are you hugely overweight or using the wrong size post? Having eliminated those possibilities have you tried roughing up the inserted portion of post with some glasspaper?

  3. #3
    Crawfishy
    Reputation:
    Join Date
    Jun 2004
    Posts
    78
    I had this problem on a new frame and did some research on it. It is usually not the post but the frame. It can be hundreths of a mm off but it is a problem. The only was to tell is to use a set of digital calipers. I found a post on MTBR were some people recommended using a coke can shim or even natural chaulk. It tried both and had no luck.

    I wasn't worried about the frame becoming something that will ever fit the VRC category so I used some Truck Bed Liner from a spray can to add some thickness to the seat tube. So far it has worked perfect.
    "98% of us will die at some point in our lives" - Ricky Bobby

  4. #4
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by mechagouki
    Are you hugely overweight or using the wrong size post? Having eliminated those possibilities have you tried roughing up the inserted portion of post with some glasspaper?
    No, no, and no. Thomson posts are ridged, so they're sort of rough on their own.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  5. #5
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by Crawfishy
    It is usually not the post but the frame.
    Since it's repeatable with two different posts, I'm pretty sure it's the frame.

    The ears look like they squeeze together, but the slot doesn't. I'll try to get some close-ups tonight, I've got a headset to install so I'll be working on the bike anyway.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  6. #6
    mtbr member
    Reputation: laffeaux's Avatar
    Join Date
    Jan 2004
    Posts
    5,983
    I have a frame where a Thomson post also tends to slip. Although the Thompson is "rough," I'm not sure it's "rough enough."

    Assuming that the post is the right size (31.8mm for a Phoenix), to make it stop slipping you need more friction between the post and frame to prevent it from sliding. Less grease on the post may do the trick. I've heard of people using chalk instead of grease. Or roughen the inside of the seat tube to create a surface with more friction. Unless, the seat tube has been reamed and is now over-sized requiring a slightly larger post, the answer is "more friction."
    Each bicycle owned exponentially increases the probability that none is working correctly.

  7. #7
    mtbr member
    Reputation: Fillet-brazed's Avatar
    Join Date
    Jan 2004
    Posts
    7,696
    Quote Originally Posted by laffeaux
    I have a frame where a Thomson post also tends to slip. Although the Thompson is "rough," I'm not sure it's "rough enough."

    Assuming that the post is the right size (31.8mm for a Phoenix), to make it stop slipping you need more friction between the post and frame to prevent it from sliding. Less grease on the post may do the trick. I've heard of people using chalk instead of grease. Or roughen the inside of the seat tube to create a surface with more friction. Unless, the seat tube has been reamed and is now over-sized requiring a slightly larger post, the answer is "more friction."

    Pretty sure they take a 31.6.

    For friction you can use dirt (may not be the best option ), toothpaste, or a grease made specifically made to increase friction for slipping carbon seatposts.

  8. #8
    IVMTB & VMBEFG Illuminati
    Reputation: Veloculture's Avatar
    Join Date
    Dec 2005
    Posts
    1,493
    i have the same exact issue with my Phoenix so you're not alone. i feel that the frame is too large for the 31.8mm. a 31.9 would probably be perfect.

    grease in binding situations can actually help hold things together. i've seen slipping handlbars on BMX bikes corrected with a liberal amount of grease. i personally wouldn't remove the grease without having something else in there that would prevent rust. beyond that i don't have a solution for you. i have not begun the task of working on my Phoenix to correct the problem.

  9. #9
    Master of the Face Plant
    Reputation:
    Join Date
    Feb 2004
    Posts
    2,901
    Quote Originally Posted by Veloculture
    i have the same exact issue with my Phoenix so you're not alone. i feel that the frame is too large for the 31.8mm. a 31.9 would probably be perfect.

    grease in binding situations can actually help hold things together. i've seen slipping handlbars on BMX bikes corrected with a liberal amount of grease. i personally wouldn't remove the grease without having something else in there that would prevent rust. beyond that i don't have a solution for you. i have not begun the task of working on my Phoenix to correct the problem.
    I had exactly the same problem. I found that using a really thick grease helped. Beyond that I actually greased the post and then sprinkled a little sand from the kids sandbox on the grease. It never slipped again. I know it is a little nuts but it worked.
    http://www.nbbikes.com/
    ^^^Best Bike Shop of MTBR 2008^^^

  10. #10
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    - Beer can shim

    - Run an undersize post like a 27 or 27.2 and use a 'problem solvers' type seat post specific shim.. maybe knurl the outside of the shim first to take up some space.

    - Knurl your current post (either hand knurl ie punch marks, or a good shop will have either a lathe or the Stein knurling tool).

    -See if you can find a 31.9 post.. maybe that would work. Use a flex hone on a drill if you need more space

    -Take it to a frame builder and either get it taken up to the next size, and/or have the ears taken off, as they provide very uneven clamping force as compared to a collar like a Salsa with a barrel nut.

    - Use grease with sand in it.. like really fine blasting sand, or get some play ground sand and sift it.

    - Get really into trials.

    -Schmitty-

  11. #11
    mtbr member
    Reputation: yo-Nate-y's Avatar
    Join Date
    Mar 2009
    Posts
    2,734
    Jeez, I had always thought Potts had better quality control.
    Somec is like the digital Zunow
    And this: http://www.youtube.com/watch?v=JD5h3y0a9AU

  12. #12
    IVMTB & VMBEFG Illuminati
    Reputation: Veloculture's Avatar
    Join Date
    Dec 2005
    Posts
    1,493
    Quote Originally Posted by yo-Nate-y
    Jeez, I had always thought Potts had better quality control.

    i can't blame him on my newly acquired frame. my frame has been to hell and back.

  13. #13
    mtbr member
    Reputation: yo-Nate-y's Avatar
    Join Date
    Mar 2009
    Posts
    2,734
    They do seem to have long lives
    Somec is like the digital Zunow
    And this: http://www.youtube.com/watch?v=JD5h3y0a9AU

  14. #14
    Fan of 'Hams
    Reputation: halaburt's Avatar
    Join Date
    Jan 2004
    Posts
    228
    http://www.finishlineusa.com/products/fiber_grip.htm

    This is an example of the stuff FB mentioned (designed for carbon applications but does the job on metal/metal seatpost situations too).

  15. #15
    Fan of 'Hams
    Reputation: halaburt's Avatar
    Join Date
    Jan 2004
    Posts
    228
    Quote Originally Posted by Schmitty
    -Take it to a frame builder and either get it taken up to the next size, and/or have the ears taken off, as they provide very uneven clamping force as compared to a collar like a Salsa with a barrel nut.
    -Schmitty-
    I have a Phoenix in with Steve now getting "re-Eared" as its prior owner thought that might be the answer too... I don't think it was. I'd try everything else on the response list here and then still think long and hard before taking a hacksaw (or line-borer) to something as collectible/valuable as a Phoenix.

  16. #16
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    Quote Originally Posted by halaburt
    I have a Phoenix in with Steve now getting "re-Eared" as its prior owner thought that might be the answer too... I don't think it was. I'd try everything else on the response list here and then still think long and hard before taking a hacksaw (or line-borer) to something as collectible/valuable as a Phoenix.

    Not advocating a hack job. Use your own discretion... if it's *that* collectible to someone, maybe it should just be retired, and then the post is a non issue....


    -Schmitty-

  17. #17
    mtbr member
    Reputation: Fillet-brazed's Avatar
    Join Date
    Jan 2004
    Posts
    7,696
    Quote Originally Posted by yo-Nate-y
    Jeez, I had always thought Potts had better quality control.

    The two Phoenixes I've had have had a perfect fit.

    And yeah, I guess they are 31.8 and not 31.6 afterall.

  18. #18
    mtbr member
    Reputation:
    Join Date
    Jan 2004
    Posts
    168
    I recognise the problem too with my Phoenix. After many years of hard service, my seatpost slips a little too. I found an easy solution. I bought a 31.8 Salsa liplock-collar and clamped this around the seatpost (shaving down a little to get it fitt even around the seatpost). This collar stops the seatpost from sinking further. Of course it also makes lowering the seatpost less fast, but this is a nonissue for me. Probably not the most elegant solution, but works perfect.

  19. #19
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    It's good to know I'm not alone. The frame has had this problem from day one. I didn't buy it new, but it had never been built when I got it.

    I have read before about the friction paste mentioned above, and seem to remember you can end up with the post stuck. That memory may be false though, but there was some downside that kept me from trying it.

    I'm definitely the right sized 31.8 post, and again, with two posts slipping, it's gotta be the frame at fault. Hanging it on the wall is not an option.

    I blame the ears, but I'm not going to hack them off. Collectible or not, that just doesn't seem to be a good idea.

    When I put the post back in (had it out to drain a wee bit of water), I carefully tightened the bolt to where the two ears came flush together, so maybe that will do it, maybe not.

    I like Pottser's idea - has the lip lock messed up the top of the seat tube any?
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  20. #20
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    Quote Originally Posted by wv_bob

    has the lip lock messed up the top of the seat tube any?
    It'd be easy enough to make a platsuc/rubber washer to go in between. make sure not to damage the post.

    You could also file some material from the inside of the 'ears', but this will only treat the symptom, and may actually make it worse by allowing you to tighten more. That style binder actually pushes inward -very unevenly- at the ears.. worst case you can actually dent the post.

    The knurling and beer can shim ideas are the best,and least obtrusive imo.

    -Schmitty-

  21. #21
    Witty McWitterson
    Reputation: ~martini~'s Avatar
    Join Date
    Dec 2003
    Posts
    5,023
    In the later years of Pheonix production, this problem was solved. Mine had no ears. Just a nice DKG seat clamp. I never had any slipping issues. If it were me, I'd send it in to Steve, have him remove the ears and use a clamp. Problem solved. Oh, and I've always found Thomson posts to be ever so slightly undersized. This certainly isn't helping you.
    Just a regular guy.

  22. #22
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by Schmitty
    You could also file some material from the inside of the 'ears', but this will only treat the symptom, and may actually make it worse by allowing you to tighten more. That style binder actually pushes inward -very unevenly- at the ears.. worst case you can actually dent the post.
    Yes, I'd thought about opening the gap between the ears, but figured all that would do is increase the odds that I'd snap them off due to overtightening.

    I've noticed what you mean about the ears pusing inward - first attempt with a bolt I used some old junk I had laying around and the ears bent it when tightened. The gr 8 bolt seems to be staying straight.

    The knurling and beer can shim ideas are the best,and least obtrusive imo.
    I'm trying to stay away from knurling, because knowing me, the odds of screwing something up are too high to chance. I don't think there's room for any shim material - the post fits right, but the frame just doesn't snug down around it enough to hold it in place.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  23. #23
    Trying to grow a mustache
    Reputation: Z-Man's Avatar
    Join Date
    Apr 2005
    Posts
    375
    Friction paste made my IndyFab/Syncro combo creak like mad, even with a salsa sp qr. I cleaned everything (grease, gunk, man milk...) off the post and frame and replaced the bent bolt on my salsa qr and it's been ok for 2 rides so far...
    Vintage-Retro-Pragmatist

  24. #24
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by ~martini~
    In the later years of Pheonix production, this problem was solved. Mine had no ears. Just a nice DKG seat clamp. I never had any slipping issues. If it were me, I'd send it in to Steve, have him remove the ears and use a clamp. Problem solved. Oh, and I've always found Thomson posts to be ever so slightly undersized. This certainly isn't helping you.
    Happened with an American Classic post too. It was even worse IIRC.

    If repaint time ever comes, I'll probably have the ears removed and a disc mount added. I'm just trying to keep it going in the mean time. The bike's still in good shape, too good to spend $4-500 bucks on for sure.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  25. #25
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by Z-Man
    man milk.
    Normally there's never a case of too much info in a technical thread, but this is a case where that surely applies.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  26. #26
    artistic...
    Reputation: colker1's Avatar
    Join Date
    Jan 2004
    Posts
    7,518
    Quote Originally Posted by wv_bob
    It's good to know I'm not alone. The frame has had this problem from day one. I didn't buy it new, but it had never been built when I got it.

    I have read before about the friction paste mentioned above, and seem to remember you can end up with the post stuck. That memory may be false though, but there was some downside that kept me from trying it.

    I'm definitely the right sized 31.8 post, and again, with two posts slipping, it's gotta be the frame at fault. Hanging it on the wall is not an option.

    I blame the ears, but I'm not going to hack them off. Collectible or not, that just doesn't seem to be a good idea.

    When I put the post back in (had it out to drain a wee bit of water), I carefully tightened the bolt to where the two ears came flush together, so maybe that will do it, maybe not.

    I like Pottser's idea - has the lip lock messed up the top of the seat tube any?
    Like Pottser i have used the clamp of an old reflector.. even less elegant but a slippin seatpost was costing my sanity.
    WTB: Bomber Z2 1 1/8 steerer, in good to excellent shape OR bomber rebuild kit.

  27. #27
    Down South Yooper
    Reputation: Plum's Avatar
    Join Date
    Sep 2004
    Posts
    1,010
    I would try the carbon assembly paste stuff first, it's cheap and easily reversible. I used it to stop a slipping thomson post in a custom spicer. I wouldn't be concerned about the post freezing with carbon paste on it, think of it as gritty grease.

    Plum
    This post is in 3B, three beers and it looks good eh!

  28. #28
    mtbr member
    Reputation: Fillet-brazed's Avatar
    Join Date
    Jan 2004
    Posts
    7,696
    Quote Originally Posted by Plum
    I would try the carbon assembly paste stuff first, it's cheap and easily reversible. I used it to stop a slipping thomson post in a custom spicer. I wouldn't be concerned about the post freezing with carbon paste on it, think of it as gritty grease.

    Plum

    I agree.

    if that doesn't work, I would try slipping in a partial aluminum can shim. You probably don't have enough room to install a full (all the way around the post) shim. If I recall, I think they add .2mm to the diameter, but you could cut a 1" x 2" section out of a can and try to slip that in on the front side of the post just to increase the clamping ability... Would be hidden if you did it right...

    That's too bad it doesn't fit right. Have you talked to SP about it? Send him an email maybe and see what he recommends.

  29. #29
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    Quote Originally Posted by wv_bob
    I'm trying to stay away from knurling, because knowing me, the odds of screwing something up are too high to chance. I don't think there's room for any shim material - .
    The 'knurling' would be getting a hammer and nail punch/drift and just go around the post (below st height) and dimple the bejesus out of the post. Each punch mark will have a small divot below the surface of the post, and will be ringed by the displaced material above the surface of the post. That ring will be what adds diameter to the post. I'd do probably 6 vertical rows at least 2 inches long with dimples every 5 mm or so.

    As for the can shim, as someone else stated it doesn't need to go all the way around (as this doubles the amount added). Just run it half way around. If it's tricky to get in, remove your binder bolt, run it in the other way.. threaded half first.. when the end of the bolt gets toward the other non threaded 'ear', insert a penny in there so that the end of the bolt runs up against the penny, and you can then use the bolt to open up the binder slot, insert shim, take out bolt, and put it back right way around.

    -Schmitty-

  30. #30
    mtbr member
    Reputation: laffeaux's Avatar
    Join Date
    Jan 2004
    Posts
    5,983
    Quote Originally Posted by Schmitty
    As for the can shim, as someone else stated it doesn't need to go all the way around (as this doubles the amount added). Just run it half way around.
    In my experience, Tecate cans make the best shims.
    Each bicycle owned exponentially increases the probability that none is working correctly.

  31. #31
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    Quote Originally Posted by laffeaux
    In my experience, Tecate cans make the best shims.



    Yup, the 5th can to be exact...

    -Schmitty-

  32. #32
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Well, I'm hoping the weather straightens up enough this weekend so I can put some miles on the bike. If so I'll know if torquing the everloving crap out of that bolt worked or not. If not, then I'll start applying the ideas posted here, easiest to most difficult, until I find joy.

    Thanks for all the suggestions
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  33. #33
    horn doggie
    Reputation: scooderdude's Avatar
    Join Date
    Sep 2004
    Posts
    847
    Quote Originally Posted by laffeaux
    In my experience, Tecate cans make the best shims.
    But their can manufacturer's quality control is so bad that wall thicknesses of each can may be a bit different from one another by a micron or two. You may have to go through several on a warm afternoon before you find just the right one to do the trick.
    Wanted:

    Potts, Potts, Potts

  34. #34
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    If you go the shim route, let me know. I have a full assortment of steel bearing shim stock from foil thickness on up. Nice b/c it's steel, and already a good size... no drunken utility knife accidents. Be happy to send some your way (they come in a kit of about 200, so pita to try a get just a couple on the market).

    -Schmitty-

    sorry, my op got truncated.. this should make more sense!
    Last edited by Schmitty; 01-23-2010 at 09:35 AM.

  35. #35
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    I may go with a shim - got to thinking and looking last night - with the drop bar I could use a little more cockpit length. The AC post has setback, the Thomson doesn't. So I might just switch back, and if I do, it'll need a shim because it's either worn, or squeezed, out of round.

    I'm about to head out now, so it's going as is for the time being. I'll try to get a photo of the bike with the final drop bar setup while I'm at it.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  36. #36
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    It didn't slip this time
    Attached Thumbnails Attached Thumbnails Slipping seat post - WTB Phoenix-img_5283_sml.jpg  

    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  37. #37
    mtbr member
    Reputation:
    Join Date
    Nov 2005
    Posts
    112
    You running the new Salsa bars in that picture?

  38. #38
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Yes, 46cm Woodchippers
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  39. #39
    mtbr member
    Reputation: Fillet-brazed's Avatar
    Join Date
    Jan 2004
    Posts
    7,696
    Quote Originally Posted by wv_bob
    It didn't slip this time

    so what did the trick?

  40. #40
    Bird watcher
    Reputation: ckevlar's Avatar
    Join Date
    Feb 2005
    Posts
    878
    cut a wooden dowel to just the right length and put it inside the seat tube and post. Perfecto, no more issues

    Quote Originally Posted by Fillet-brazed
    so what did the trick?

  41. #41
    mtbr member
    Reputation: Fillet-brazed's Avatar
    Join Date
    Jan 2004
    Posts
    7,696
    Quote Originally Posted by ckevlar
    cut a wooden dowel to just the right length and put it inside the seat tube and post. Perfecto, no more issues

    haha. now there's an idea that was never brought up!

  42. #42
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    Quote Originally Posted by Fillet-brazed
    haha. now there's an idea that was never brought up!

    Too bad it would rest on the upper bottle braze-on anb break the braze-on, if not the st as well.


    -Schmitty-

  43. #43
    mtbr member
    Reputation: Fillet-brazed's Avatar
    Join Date
    Jan 2004
    Posts
    7,696

    good thinkin

    Quote Originally Posted by Schmitty
    Too bad it would rest on the upper bottle braze-on anb break the braze-on, if not the st as well.


    -Schmitty-

    good thinkin, but I'm pretty sure it was just a joke. If you wanted to really do this you could use a dowel thin enough to clear the bottle bosses.

    hey and you could even put some wood screws through the water bottle bolt holes into the dowel to make it even more sano!

    the previous sentence may contain sarcasm and may be a joke.

  44. #44
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    1,640
    Quote Originally Posted by Fillet-brazed
    good thinkin, but I'm pretty sure it was just a joke. If you wanted to really do this you could use a dowel thin enough to clear the bottle bosses.

    hey and you could even put some wood screws through the water bottle bolt holes into the dowel to make it even more sano!

    the previous sentence may contain sarcasm and may be a joke.
    jbweld

    -Schmitty-

  45. #45
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by Fillet-brazed
    so what did the trick?
    No change, just careful tightening. It may slip yet.

    Don't forget that to use a wooden dowel, use treated lumber otherwise the water that collects in the seat tube will rot the bottom of it.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  46. #46
    mtbr member
    Reputation: Fillet-brazed's Avatar
    Join Date
    Jan 2004
    Posts
    7,696
    Quote Originally Posted by wv_bob
    No change, just careful tightening. It may slip yet.

    Don't forget that to use a wooden dowel, use treated lumber otherwise the water that collects in the seat tube will rot the bottom of it.

    good point. Do they even make pressure treated dowels? I think we should change to PVC pipe and save weight while we're at it.

  47. #47
    mtbr member
    Reputation: yo-Nate-y's Avatar
    Join Date
    Mar 2009
    Posts
    2,734
    Forget standing the post on top of a dowel. The surest solution would be set the height by drilling through the seat tube and post then placing a bolt. Clean and tidy!
    Somec is like the digital Zunow
    And this: http://www.youtube.com/watch?v=JD5h3y0a9AU

  48. #48
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by Fillet-brazed
    good point. Do they even make pressure treated dowels? I think we should change to PVC pipe and save weight while we're at it.
    It might be possible to size the PVC so it can flex to the side inside the tube, adding a bit of suspension.

    Quote Originally Posted by yo-Nate-y
    Forget standing the post on top of a dowel. The surest solution would be set the height by drilling through the seat tube and post then placing a bolt. Clean and tidy!
    :
    Yeah but then you'd have to be taking the bolt out all the time to pull the post and drain the water. I guess I could leave the bolt at the original clamp out, so maybe it's as broad as it is long.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  49. #49
    mtbr member
    Reputation: yo-Nate-y's Avatar
    Join Date
    Mar 2009
    Posts
    2,734
    You could affix a small umbrella above the bolt

    Has it slipped now that you've been out on it again?
    Somec is like the digital Zunow
    And this: http://www.youtube.com/watch?v=JD5h3y0a9AU

  50. #50
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by yo-Nate-y
    You could affix a small umbrella above the bolt

    Has it slipped now that you've been out on it again?
    I tried putting a bit of road tube over the post and then down over the top of the seat tube, but cut it too short to cover everything and fit tight.

    I've only been out on it once since the change. It may take an offroad ride to make it slip again. If so, it's going to be a while.
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

  51. #51
    Needed Less ~ Did More
    Reputation: Singlespeedpunk's Avatar
    Join Date
    Jan 2004
    Posts
    1,008
    Try some carbon assembly paste (used on Carbon seat posts and / or carbon frames) as this will prevent corrosion between the frame and post but grip a lot better than the regular grease / copper slip.

    Worth a shot and will only cost a few $ and its removable
    SSP
    "Put any one on one of these singlespeed bikes and they could not help but have fun"
    -
    Otis Guy talking about klunkers c1976

  52. #52
    mtbr member
    Reputation:
    Join Date
    Jan 2011
    Posts
    2
    Dead thread, but I thought I'd post up my solution for the classic Phoenix slipping seat post, for others to learn from. I've had my Phoenix since 1997, with an original seat post that slipped occasionally until I solved it by doing the following. Some of the Phoenix purists might disapprove, but I delicately took a dremel reinforced cut-off wheel and widened the seat tube slot and the insides of the "ears." Took it off iteratively--riding and testing between very fine cuts-- until it stopped slipping. The downside is that the bolt bends through the ears a little when it's really tight. I'm not too worried about the bolt easy to replace, and no problems yet.

  53. #53
    gobsmacked Moderator
    Reputation: girlonbike's Avatar
    Join Date
    Apr 2008
    Posts
    8,757
    Hollister used friction paste on mine. Worked like a charm.

  54. #54
    I'm just messing with you
    Reputation: wv_bob's Avatar
    Join Date
    Sep 2005
    Posts
    5,423
    Quote Originally Posted by Ashes
    I delicately took a dremel reinforced cut-off wheel and widened the seat tube slot and the insides of the "ears."
    That's very much like what Steve Potts recommended to me via email, except he suggested using a file instead. That would work better for me anyway, because with a power tool in my hand, doing anything delicate is out of the question.

    So I went out and bought a decent set of slim files to take care of the situation, but it hasn't slipped since I asked Steve about it months ago. As long as it'll hang tough like it is, I'm not taking the post out to mess with it. I'll always have the tools though, so I'm ready to screw it up I mean fix it if it slips again
    Chasing bears through the woods drunk with a dull hatchet is strongly not advised

Members who have read this thread: 0

Posting Permissions

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

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2020 VerticalScope Inc. All rights reserved.