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  1. #1
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    Stumpy stock seatpost problem

    I have a 10' Stumpy Comp 29er. The stock seatpost has been giving me quite the problems as of late and I was wondering if someone else is having the same problems. Pretty much what it boils down to is that I am an uber-clyde-lardass (300lbs, 6' 1") after riding for about an hour, the seat clamp starts to loosen or get torqued, and my seat starts to tilt upwards instead of staying level. Now I know this problem is most likely because of my plumpness, but I was hoping maybe it was some sort of defect. I usually torque my stuff the correct way. I had an old thomson seatpost that I have been using and that never gives me problems. Although I believe the stock seatpost is a setback. My thomson is not. What do you guys think I should do.

  2. #2
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    Quote Originally Posted by Delete_Yourself
    I have a 10' Stumpy Comp 29er. The stock seatpost has been giving me quite the problems as of late and I was wondering if someone else is having the same problems. Pretty much what it boils down to is that I am an uber-clyde-lardass (300lbs, 6' 1") after riding for about an hour, the seat clamp starts to loosen or get torqued, and my seat starts to tilt upwards instead of staying level. Now I know this problem is most likely because of my plumpness, but I was hoping maybe it was some sort of defect. I usually torque my stuff the correct way. I had an old thomson seatpost that I have been using and that never gives me problems. Although I believe the stock seatpost is a setback. My thomson is not. What do you guys think I should do.
    Common problem man. Same thing happened on my 09. Its a single bolt post and after a while no matter how hard u crank that bolt it won't hold those clamp cups in there to prevent the tilt when you take a hit. Best thing you can do is stick with a two bolt clamp post such as the thomson and there are a few others on the market as well. Good luck.

  3. #3
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    that's about what I figured. A little disappointed to be honest, as it's my first Specialized, and I thought they were known for their quality components? On the other hand, my fatassness doesn't help matters. Anybody want to trade me a setback thomson for my standard?

  4. #4
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    Quote Originally Posted by Delete_Yourself
    that's about what I figured. A little disappointed to be honest, as it's my first Specialized, and I thought they were known for their quality components? On the other hand, my fatassness doesn't help matters. Anybody want to trade me a setback thomson for my standard?
    Not completely due to you being a big guy. Most aluminum components don't have a "strict" weight limit. When you get into carbon...yeah. Specialized is known for their top quality frames and overall spec of the parts on their bikes. Where they fall short is with some of thier "house brand" or "custom" items. They are large so they work with part companies and get them to modify (usually a slight decrease in performance or quality) existing products for their use on their bikes. Don't fret, most bikes with the exception of ultra-upper end stuff usually have posts, bars and stems that crap out fairly quickly. Spend what you can on a nice used or new two bolt clamp post and ride the hell out of it. You can't go wrong with a Thomson. It will be just as solid 10 yrs. after you purchased it.

  5. #5
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    I have a specialized SJ FSR with the stock seatpost and I am also a fatty boombaladdy (6'2", 295). I have not had the problem that you are describing but I have noticed that after about an hour my post is 1 or 2 inches lower. My post is not set back, it is straight. I wonder if the rearward leverage has something to do with it.
    Good luck my heavyweight brother!

  6. #6
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    Noticed that the straight post on the '11 SJ FSR Test Bike I had this past weekend kept dropping around an inch or so every half hour of riding. Finally just cranked the torque up on the clamp bolt and didn't have an issue again. I'm "only" 6' 2" ~200lbs though.

    Sounds like your issue is more w/ the saddle clamp however. Is it one of those single bolt deallies? I'd say either way, try upping the torque on the bolt(s).

    Keep in mind that most bike companies seem to assume the average rider is a delicate little flower/anorexic super model and weigh <175lbs regardless of the size of the frame they're buying.

  7. #7
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    it is a single bolt deal. I have upped the torque, but the same problem persists. I noticed on the new Stumpy EVO frames they come with a Thomson setback right from the factory. Specialized way of fixing said problem? I emailed Specialized to see if they would replace mine with a thomson setback, or at least give me a discount on one due to their product failing. We shall see, my hopes aren't that high though.

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    make sure the bolt is lubed.

    I never had a problem with my stock post, but when I got a replacement for my command post the LBS installed it and it was doing what you describe. I tightened it 3 times on that first ride and it still moved. I had installed the command post originally and remembered that the instructions say you need to lube the bolt. Once I did that the thing worked like a champ.

    So try lubing your bolt and see if that helps. Kind of makes sense that this would help since less friction implies more clamping force for the same amount of applied torque.
    TEX

  9. #9
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    Texas, that does make sense to some extent. I'll probably just stick to the thomson I have on there right now. Still haven't heard back from Specialized, so who knows. Can't go wrong with a thomson! Specialized is even putting them on their EVO framesets now.

  10. #10
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    Quote Originally Posted by h_daddy
    I have a specialized SJ FSR with the stock seatpost and I am also a fatty boombaladdy (6'2", 295). I have not had the problem that you are describing but I have noticed that after about an hour my post is 1 or 2 inches lower. My post is not set back, it is straight. I wonder if the rearward leverage has something to do with it.
    Good luck my heavyweight brother!
    If you've got a quick release seatpost clamp then they don't fasten as tightly as an allen key seatpost clamp. A quick release clamp is handy for quickly adjusting seatpost height but will let the saddle slip.

    What you can do to address this problem is to swap the seatpost clamp for an allen key one, put some Tacx carbon assembly paste on the seatpost to increase friction and screw the plastic clamp from a rear reflector or light as an additional stop on the seatpost to stop it slipping down in the frame.

    Allen key seatpost clamp (the Stumpjumper FSR uses a 34.9mm size):
    http://www.hopetechnology.com/products/sc_02.htm

    Tacx carbon assembly paste
    http://www.tacx.com/en/producten/fie...asta/index.dot

    Seatpost light bracket (use the reflector bracket that came with your bike or they're cheap from a bike shop)
    http://www.wiggle.co.uk/cateye-ld170-bracket-and-clamp/

    If the saddle clamp is slipping then it's better to replace the seatpost with a two bolt one like the Thomson. It saves a lot of hassle.
    Last edited by WR304; 11-10-2010 at 08:40 AM.

  11. #11
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    You can get an inexpensive 2 bolt clamp. I've bought them at a LBS for around $20 before. Being 30.9 it may be a bit more challenging to find, but I'm sure it can be ordered.

  12. #12
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    Something like a Race Face Ride XC seatpost (30.9mm) is a cheaper two bolt alternative to a Thomson Elite seatpost if you don't need any setback.

    http://www.wiggle.co.uk/race-face-ride-xc-seat-post/

  13. #13
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    Quote Originally Posted by WR304
    If you've got a quick release seatpost clamp then they don't fasten as tightly as an allen key seatpost clamp. A quick release clamp is handy for quickly adjusting seatpost height but will let the saddle slip.

    What you can do to address this problem is to swap the seatpost clamp for an allen key one,

    Ditto, my post would slip down on every ride no matter how tight I got it. I then put an allen bolt clamp (Salsa) on it and now it doesn't move.

  14. #14
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    just for the record, it wasn't an adjustable. Just standard one bolt setback that comes with the bike. Thanks so far for the replies!

  15. #15
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    had same problem on my 09. took it appart and cleaned out the grease with brake clean and have not had any more problems. Grease ona part that you dont want to move did not make any sense to me!

  16. #16
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    I weigh 200 (started out at 225 4 years ago)
    I have learned that the cycling industry designs for 160 lbs
    I wear everything out quicker than a lighter person
    If Specialized designed for heavy weight riders the bikes would
    never sell because of cost/weight
    I figure my XTR drivetrain costs me about $3 per ride when you factor in wear/tear.
    the forces generated by 300 lbs on a downhill trail must me be
    huge compared to 160 lbs. (hey physics students tell use how much)

    Quote Originally Posted by Delete_Yourself
    that's about what I figured. A little disappointed to be honest, as it's my first Specialized, and I thought they were known for their quality components? On the other hand, my fatassness doesn't help matters. Anybody want to trade me a setback thomson for my standard?

  17. #17
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    got my answer from Specialized. Take it to your LBS that you bought it from. Problem is, turned out those guys aren't reliable so I'm pretty much stuck with my buddy's thomson for now until he needs it back. Gonna have to look for a thomson setback I guess.

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    I had the same problem, and I weigh less than 160. 155 or so. I just did a google search for it and found this thread.

    Very annoying. This is on the 2010 Epic Comp. That's a lot to pay for a bike with a seat that doesn't work. C'mon Specialized.

  19. #19
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    Yeah, two bolts are definitely more reliable and highly adjustable.

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    I don't know about that. One bolt head clamps are still good, they just have to be well designed. As with most companies, the saddle/seatpost/collar clamp/pedals etc are the components companies hold back on to reduce costs so as to spend more on frame design, shocks, wheels etc.

    Just get a new seatpost or drill out the holes in the mounts/brackets and put a bigger bolt and nut on the end to get a higher torque.

    If it's a lay back design, try shifting the saddle further forward on the head clamp (not too far though) or try sitting further forward too.

  21. #21
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    Wound up getting one of these seat posts on my Camber Pro. One thing I noticed is the saddle clamp bolt is specced for 101 in/lbs (~12Nm) which seems pretty darn high, high enough that I wouldn't get there using a standard sized allen wrench. Bolt was nowhere near this level of torque when I took delivery. When I made some adjustment to the saddle angle I went ahead and cranked this bolt down to 11Nm w/ a ratchet style torque wrench and even that was taking a good bit of effort on the last couple half turns of the bolt.

    I definitely like the idea behind the design of this single bolt clamp, seems a good deal easier to dial in the angle IMO than other two bolt clamps I have used. We'll just have to see if holds for me in the long run. No issues in my couple of rides on it so far. If it's slipping all over the place after a while I could see the stability of a 2 bolt clamp far out weighing the convenience of the single bolt.

    Definitely nothing wrong w/ a Thompson post. Would be nice is Specialized would pony up w/ one for you or at least give you some kind of kickback for the stock post that you can't use..

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