[stevenb]

Just got a new Specialized Roubaix. Its a full carbon bike with a carbon seatpost, that when set to proper torque begins to slip down after 20 min or so on the bike.
Any remedies?
Anyone else have this problem?

 

[lousylegs]

Just got a new Specialized Roubaix. Its a full carbon bike with a carbon seatpost, that when set to proper torque begins to slip down after 20 min or so on the bike.
Any remedies?
Anyone else have this problem?

Did you grease the seatpost or seat tube before putting it in?

That would probably be the first thing that I would look at.

 

[Freefall]

I had the same problem on the same bike. I changed out the seat post clamp to a Salsa, problem solved.

 

[Kerry Irons]

Hair spray

Just got a new Specialized Roubaix. Its a full carbon bike with a carbon seatpost, that when set to proper torque begins to slip down after 20 min or so on the bike.
Any remedies? Anyone else have this problem?

As lousylegs noted, you might want to clean off any grease, though this may result in corrosion issues if you have an aluminum insert in the seat post. And Freefall may be right that a new seat collar would help. Another thing to try is to shoot some hair spray on the post before you insert it in the frame. Once the hair spray dries, it will help a lot with preventing seat post slip.

 

[botto]

as kerry wrote, the hairspray technique is one way to deal with it. i've also read that people have 'roughed up' the clear coat with 220 sandpaper.

i've tried the hairspray over the weekend (new tcr comp w/cf post). it slows the slip, but hasn't eliminated it yet.

Just got a new Specialized Roubaix. Its a full carbon bike with a carbon seatpost, that when set to proper torque begins to slip down after 20 min or so on the bike.
Any remedies?
Anyone else have this problem?

 

[The Carlster]

yes, the sandpaper trick - be careful not to sand where the post is above the seattube as it's rather unsightly. Heavy grit sandpaper works best.

 

[80sguy]

Have you tried a torque wrench?

I just went out and bought a torque wrench from my LBS to try and solve this exact issue on my Roubaix. I set the wrench to less than the torque recommended by Specialized (45 in-lbs) and began tightening. I did not get to the torque when the head of the bolt snapped right off! There was no damage to the post, frame, collar or the dingle-hopper the bolt threaded into. Just took it back to my LBS and they replaced the bolt. Obviously it was a good thing the bolt failed before the collar/frame/post. I've checked the torque wrench against several other calibrated wrenches and it is within 5% of the expected settings. You think the seat collar bolt is robust enough to hold the specified torque? I have not tried again as I now know you can give the collar bolt a good twist without causing damage. Has anyone else tried to tighten the collar to specification?

 

[boon]

i had the same problem with the Specialized Roubaix. Then i decided to get a torque wrench (cheap beam type) and that solved the problem. now i know what 50in/lb feels like. by the way, there was no grease on the seatpost so the problem was an inproperly tightened seatpost clamp.

boon

 

[divve]

You can use Dynamic assembly paste. It's a gel like substance with fine plastic granulates suspended in it. The Tacx distributor in the US may have it (QBP).

 

[MB1]

Drill a hole through the seat collar and seatpost and install a 1/4" bolt.

Just got a new Specialized Roubaix. Its a full carbon bike with a carbon seatpost, that when set to proper torque begins to slip down after 20 min or so on the bike.
Any remedies?
Anyone else have this problem?

Or do the smart thing and take it back to where you bought it.