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Discussion Starter · #1 ·
So I am swapping out the aluminum seatpost in my titanium bike for a carbon seatpost (enve 2 bolt). Enve has clear instructions on how to install the saddle, including torque specifications, but nothing on inserting the seatpost into the frame. Do I use any gel/compound/lubricant? I've read conflicting advice. And what torque do I tighten to?

Thanks for your advice.
 

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So I am swapping out the aluminum seatpost in my titanium bike for a carbon seatpost (enve 2 bolt). Enve has clear instructions on how to install the saddle, including torque specifications, but nothing on inserting the seatpost into the frame. Do I use any gel/compound/lubricant? I've read conflicting advice. And what torque do I tighten to?

Thanks for your advice.
Carbon paste is typical for a seat post if that's what you are asking about. You ask about the torque but you mentioned previously they have clear torque specifications, so I'm confused as to why you wouldn't use their specs?
 

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If either material is carbon, then anti-seize compound or carbon paste is recommended. Grease has the potential to react with the sealed surface of carbon.

If your seat collar doesn't have a listed torque spec, then use the following guide:

Torque specs can vary based on the diameter and thread pitch of the bolt. Obviously, overtorquing and cracking the seatpost is a consideration. Salsa recommends 8Nm or lower if the frame manufacturer lists a lower spec. The range is usually 5-8Nm.

Tightening the bolt until the seat is immovable is not necessary. It only need to not slip downward. The Barnett's Manual specifies tightening the bolt until the seat will resist 50 lbs. of twisting force to rotate the seatpost in the frame.
 

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You use lots of this stuff. Completely cover the portion of the post going in the frame with it. It's a grease that has particles in it and it commonly called "friction paste" or "carbon paste" or something like that. It's used anywhere carbon is clamped.


As for the torque spec, it should be written on the seatbolt binder clamp that came with the frame. If not it's in the manual that came with the frame. Usually 5-6 Nm.
 

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Discussion Starter · #5 ·
You use lots of this stuff. Completely cover the portion of the post going in the frame with it. It's a grease that has particles in it and it commonly called "friction paste" or "carbon paste" or something like that. It's used anywhere carbon is clamped.


As for the torque spec, it should be written on the seatbolt binder clamp that came with the frame. If not it's in the manual that came with the frame. Usually 5-6 Nm.
Thanks, I'll go with 5-6Nm and get some carbon paste. The frame was custom and didn't come with a manual, and I replaced the clamp early on so its color matched the frame, so no instructions.
 

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Most high quality seat clamps have limits of 4.5 or 5nm. I'd start there. A thin layer of carbon assembly paste is enough; you don't need to slather it on.
Often the clamp has to be reversed so the slot is not at the back. The corners of the slot can damage the post when it flexes.
 

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Discussion Starter · #7 ·
Thanks for all of your help. Used carbon paste and tightened clamp to 5 Nm.

This forum is so useful.
 

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Grease has the potential to react with the sealed surface of carbon.
Not really. There are lots of carbon parts that are continuously in contact with grease and oil with no issues. And carbon assembly paste is essentially grease with grit in it. I've been using grease on a CF seatpost for more than a decade with zero issues.

To the OP: your Ti frame may have an aluminum collar installed in the seat post. Grease will work fine unless the post slips when you tighten it properly. If that is the case, then switch to assembly paste. Experience teaches that seat posts should always be greased. If you want things to last, all contact surfaces should be greased.
 

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Salsa recommends 8Nm or lower if the frame manufacturer lists a lower spec. The range is usually 5-8Nm.
8Nm seems too high. I would definitely try the low end first.
 
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