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Retaining Seatpost in Rockhound Frame
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Author:  pro1200 [ Mon May 29, 2006 7:49 pm ]
Post subject:  Retaining Seatpost in Rockhound Frame

I'm having trouble keeping the seatpost in place on my new Rockhound. I wasn't using any grease on it and a popping noise developed in the clamp area so my LBS greased the quick clamp and post and the popping went away but now the post won't stay in place. Is there any special procedure for keeping a post in place with a steel frame?

Author:  Dawgs [ Mon May 29, 2006 8:45 pm ]
Post subject:  Slipping Seatpost

No there is not. I have had my rockhound since 2003 and the seatpost slips on every ride. I have used the salsa clamp that Gunnar recommends, I have used numerous other clamps, different posts, etc. Nothing works. It's a shame, because this bike rides like a dream, but a slipping seatpost ruins a good ride. I finally got tired of it and shimmed it with a small piece of aluminum flashing. The seatpost no longer slips, but you should not have to do something like this to such a nice frame just to get a good ride. I wish I could get this problem fixed correctly but I assume it is something that affects everyone and not just me.

Author:  pro1200 [ Sat Jun 03, 2006 6:29 pm ]
Post subject: 

Update - My dealer installed a RaceFace Deus XC post and it is staying in place. Evidently there was something about the Thomson post that kept it from staying put.

Author:  Dave Hellekson [ Mon Jun 05, 2006 9:27 am ]
Post subject: 

Thanks pro1200!

Hi Dawgs,

There can be a number of causes for post slippage:

Inadequate seat post clamping force (via torque or design).
Undersized seatpost.
Improper anticorrosive agent (too slippery).
Oversized seat tube I.D.
Seatpost design (tube deformation).

Have all of these items been evaluated? Your post should not slip. And if it does after looking at these items then give us a call to evaluate the frame for proper seat tube I.D. and if it passes our lock-down test. We test every frame for seatpost lock-down before we paint them.

Let us know.

Author:  pro1200 [ Sun Aug 13, 2006 12:25 pm ]
Post subject: 

This is the latest chapter in my pursuit of a seatpost that stays in place and is quiet and is directed more to Dave. After a couple of months of use the Deus XC post is popping and has lost some of the coating, making me think the O.D. has changed. I applied an anti-seize paste to it (Permatex) and the popping stopped but I now have slippage but not as much as I did with the Thomson post and Mobil 1 grease. My theory is the noise is caused by motion between the post and seat tube I.D. and the lube quiets this rubbing. Is there a lube that will quiet things but not reduce the coefficient of friction enough to prevent retention? As a footnote: all the wierd things that can happen to a machine happen to me so this is not an unusual situation for me.

Author:  Dave Hellekson [ Mon Aug 14, 2006 9:57 am ]
Post subject: 

Thanks for the follow up. It sounds like the post has deformed. Check into an interesting product we are playing with and have had some great feedback, so far: Syntace friction paste. It has a higher coefficient of friction, prevents corrosion (the intent of lube here), and actually lowers the amount of torque (approx 30%) needed to hold a post in place; hence may reduce deformation especially on light weight carbon and alloy posts.

http://www.syntace.com/index.cfm?pid=3&pk=1347

Quote:
DYNAMIC Assembly Paste

As a trend-setting innovation in the bicycle market, the new assembly paste from DYNAMIC is indispensable whenever high quality carbon and aluminum components have to be assembled.
This paste has a strong lagging effect without any tendency to gum up or stick. This permits the tightening torque at the clamping point to be reduced by up to 30%, so there is no longer any danger for the clamping bolts being overturned. Ensuring undiminished locking properties, the paste relieves stress on sensitive carbon surfaces, prevents damage to the fibers and eliminates cracking.
The assembly paste ensures maximum protection against corrosion and is highly resistant to spray. It can be used for all carbon, aluminum and steel connections requiring 100 per cent reliable locking and protection against corrosion.


- Seatpost
- stem, handlebar
- Inside bearing bushes, pedals, cranks
- Screw threads

- Water resistance: high
- Viscosity: very high (at 20°C)
- Coefficient of friction: very high

Order numbers: F-023 for 80 gr. tin / F-023B for 400 gr. tin

Please find hereinafter a detailed description of the main properties of the assembly paste:

CHARACTERISTICS:
The paste is designed as a highly resistant parting compound and not primarily to be used as a conventional lubricant.
Highly resistant to mechanical load, the product can be used as a 100 per cent reliable parting agent. As there is no contact between the friction surfaces, there is no danger of two pieces of metal “welding together” or c
ceramic and plastic surfaces suffering from material breaking out.
At temperatures from – 50°C to + 150° C the product shows a constantly high coefficient of friction ( ˜ 0,1 μ ) which effectively prevents assembled parts from loosening.
The paste is neutral to copper and aluminum alloys, steel and synthetic material.

RANGE OF APPLICATION:
Assembly of bolted or clamp connections which are exposed to high mechanical load, but should not loosen or move.
Assembly of threaded pins exposed to high load which cannot be locked by a screw fastener, but should not seize solid and should be easy to release even after prolonged use (at temperatures up to approx. + 600°C [dry lubrication]).

USE:
Prior to applying the paste remove dirt particles (dust etc.) and lubricant residues from the surfaces to be treated.
Then apply a thin and even coat of DYNAMIC assembly plate to the cleaned surfaces using a brush or a lint-free textile or leather cloth.
Close tin after use. Storage life: 10 years if stored in accordance with instructions.
Stir paste before use!

Author:  Peek the Geek [ Mon Aug 14, 2006 10:43 pm ]
Post subject: 

Any idea where the Syntace Friction Paste can be bought here in the states?

Author:  Dave Hellekson [ Wed Aug 16, 2006 10:53 am ]
Post subject: 

We got ours through Ochsner Intl in Chicago. Your shop can get it for you. I will add an item number here to make it easy to order..

Author:  pro1200 [ Mon Oct 09, 2006 9:09 am ]
Post subject: 

Yet another update - I got my paste through my LBS here in Minneapolis and the stuff works! I would never have guessed that a paste like liquid could prevent a seatpost from slipping. Thanks for the suggestion Dave!

Author:  T.J. [ Mon Oct 12, 2009 4:21 am ]
Post subject: 

I am resurrecting this thread because I recently went through the same troubles. My Thomson seatpost started slipping. I cleaned the seat tube and the seatpost and applied a light coating of grease, just like on every other bike I have owned. The seatpost still slipped, so I tried torquing the seat post clamp a little more. I pulled the threads out of the nut. I took the clamp apart to see if I couldn't find another nut and I noticed that the bolt had been turning against the bottom of its hole. I don't know if that had anything to do with the stripping of the nut threads or not. I chased the hole all the way through the other side of the clamp and found another nut. My clamp now works like a champ - it just looks a little shady.
Has anyone else had similar problems?
I ordered a WOODman Death Grip clamp in the 29.8 mm size after two guys at my LBS (in Germany) told me that I should not use a 30.0 mm clamp. My feeling is that 0.2 mm isn't enough of a size difference to cause a problem.

Author:  seat_boy [ Sat Oct 30, 2010 7:43 pm ]
Post subject: 

I've had three Gunnars, and everyone featured a slipping seat post and chippy paint. I can't do anything about the paint, but on all the bikes I finally just shimmed in about a 1" wide strip of Coke can to stop the slipping.

I've tried different posts, different clamps, grease, no grease, chalk, dirt, etc. The Coke can works best. I guess Pepsi might work as well, but I wouldn't risk it :wink:

Author:  hgrd [ Mon Nov 08, 2010 2:56 am ]
Post subject: 

Hi!
After experiencing slippage, I've used a thin layer of tooth paste with great success. Does anyone think there is reason to fear that the tooth paste might be corrosive?

Author:  richardschwinn [ Mon Nov 15, 2010 11:50 pm ]
Post subject: 

Toothpaste. It's creative solution, but since it's water based, there will be two problems. First, it's water soluble and can wash away. Second, as a water based material it could also include chemicals that might lend themselves to corrosion.

Syntace friction paste is designed to be non-corrosive and is a much better play.

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