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  1. #1
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    my seat keeps slippin down when i ride...

    slips like half an inch. any of u had this issue? is it the clamp or the post?

  2. #2
    Former Bike Wrench
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    Could be a few issues:
    -Is the post the right size for the seat tube. I've owned more than one bike that said it was made for one size (26.8mm for instance) but actually measured out a size larger (27.0 for instance). Most LBS will have a measuring tool for this.

    -Is the seat clamp lined up with the seat tube slot. Most work best when the open part of the clamp matches the slot.

    -Are you using grease or friction compound (for carbon posts) on the post. A thick grease will actually help the post stay put. If its still slipping, sometimes a little dirt on the grease can help.

    Try some of these

  3. #3
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    i dunno the specifications of my post...its the one that came with my giant rincon...i think i will put a lil firt on it.. i was really wondering if there were any seat post that help prevent slippage that any of you have tried...

  4. #4
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    my suggestion

    is to get a thomson seatpost. They're widely regarded as the best out there. I have a hope quick release seatpost collar, and that works great for me. Some say Salsa works well too. My syncros was garbage. If it helps, I'm 6'4" or so and 295 geared up (pads, water, etc.)

  5. #5
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    I would "flex-hone" your frame, maybe even have it reamed. That would take out any imperfections which prevent the frame from clamping down.

    I did once switch from a no-name to a Thomson post to resolve my problem, but in the meanwhile, I used a simple plastic reflector clamp right above the seat clamp. It kept the post from slipping.

  6. #6
    Former Bike Wrench
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    While I agree that Thompson makes a great seatpost...its not necessarily a solution to a slipping post. I personally had a Thompson that I could not get to stop slipping. It was the correct size that the frame was spec'd for, but it turned out the frame was slightly off (only 0.1mm). Even with a Salsa Lip Lock, it would not stop slipping.

    So I eventually chose to ream and hone the seat tube and use a 27.2mm (from 27.0mm) which worked fine.

  7. #7
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    recommend a model of thomson for a clyde?

  8. #8
    Fat boy Mod Moderator
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    i've read seatposts and tubesets have a +/- 0.1mm amount of play... so if a 27.0 seat tube runs to the larger size (27.1m) and you have a 27.2 seatpost that is a little small (27.1) suddenly a 27.2 post fits the 27.0 tube... sometimes you get it where a tube is 27.2 and it's on the large size (27.3) and have a post on the small size (27.1) which will cause obvious slip problems...

    the easiest and cheapest fix i've seen outside is the old reflector holder trick, get your post to the right height then drop the reflector thingie sitting against the clamp...

    a good clamp also goes a long way towards keeping things tight...
    - Surly Disc trucker
    - '82 trek 560 roadie

  9. #9
    Fat boy Mod Moderator
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    Quote Originally Posted by DeVianTiCoN
    recommend a model of thomson for a clyde?

    Elite is what I use... just need to know if you need a setback or not (you prob have a setback on there stock... just all at the top with the clamp instead of in the tube like thomson)
    - Surly Disc trucker
    - '82 trek 560 roadie

  10. #10
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    I too had the slipping seatpost syndrome. After some patience and ebay sniping, I was able to get a Thomson elite seatpost and Salsa QR clamp for under $40. No more slipping!

  11. #11
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    This is a common issue for clydes.

    The solution that worked for me was a Hope Quick Release seatpost clamp. I like this b/c I do like to drop my seat for long descents. I would try this first, as I've heard that it worked for many Clydes. If it didn't work, but i bet it will, then you could look into reeming. I don't see why a Thomson seatpost would hold better and that seems like an expensive piece of bling for a Giant Rincon.

  12. #12
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    Quote Originally Posted by tenbsmith
    I don't see why a Thomson seatpost would hold better and that seems like an expensive piece of bling for a Giant Rincon.
    The Thomson actually has small ridges machined into the post, so it seems to get better "clampage." I got the seatpost first, and probably would have been fine with just that. However, I found a good deal on the Salsa clamp and got it. The salsa is definitely beefier and has more contact area than my old QR did.

    To the OP, I would definitely try a good clamp only before the seatpost, if your current seatpost is working for you. My old seatpost was a one bolt design, and probably set too loose at the bike shop. I took an unexpected big hit while seated and the seat tilted back, and effectively gouged out the aluminum. It never seemed to have proper bite after that.

  13. #13
    Lionel Hutz, Esq.
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    I've fixed this problem with a light dusting of some fine trail dirt. Certainly worth a shot and it won't cost you anything.
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  14. #14
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    Quote Originally Posted by Thirdrawn
    I've fixed this problem with a light dusting of some fine trail dirt. .
    that also works on a nagging girlfriend who complains you spend to much time on the trials

  15. #15
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    i had a rear reflector i removed but i think i will put it back on cuz it adds extra support.. i dont recall having this issue when i had it on.. il see how that works..

  16. #16
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    Changing seatposts might solve a borderline problem, but not the underlying cause which is poor clamping.

    With the exception of carbon posts whose top coat is a low friction material, all seatposts have about the same coefficient of friction and so are equally likely to slip.

    The first step is to examine the clamp, when tightened. If the post is slightly undersized (or the frame is slightly oversized) the ears may touch, and prevent the clamp from closing effectively regardless of how hard you try. After checking that you have the right diameter post, you might file a bit from the inside of the ears to allow the collar to close a bit more.. Also some QR clamps are of poor design and not able to apply enough force for heavy riders.

    The other problem is that some people do too good a job greasing the post, or use too stiff a grease. I know this is obvious, but grease reduces friction and makes things slip.

    Greasing posts was necessary to prevent corrosion when fitting non-anodized alloy posts into steel frames, and does little or no good with anodized or carbon posts. The only result of applying grease to the clamping area it to significantly raise the clamping force required.

    Use a solvent to remove all the grease from the post and the top two inches (the clamping zone) of the seat tube. Carefully apply grease to the inside of the frame not allowing any to touch the top 2". This will help protect the BB by preventing water seepage. Insert the post twisting it in to spread the grease, but do not go beyond your desired seat height, since you don't want to pull it up and bring grease back to the clamping area.

    If you plan on moving the seatpost up and down a lot, either assemble everything dry, or use a coating of light oil or a very light grease like lubriplate.
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  17. #17
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    [QUOTE=aika]is to get a thomson seatpost. They're widely regarded as the best out there.[QUOTE]

    The best, but not the strongest. Thompson posts are designed not to snap / fail, but they WILL bend (in a safe, controled manner), and its not even hard to to. I've done it, on my freeride hard tail, without even hurting myself- and I only weigh 180 lbs!

    A stronger (and price / weight comperable) alternative is the Titec El Norte. I bought one because it is the ONLY post warentied against bending that I could find. I also discovered that its a very precise fiting post with a good sandblasted / anodized finish that is very reisistant to slipping once clamped.

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