How much to tighten CF seatpost?

[101RoadRider]

Just wondering if it matters how hard you tighten a carbon fiber seatpost?
will it crack?

 

[badkarma]

Just wondering if it matters how hard you tighten a carbon fiber seatpost?
will it crack?

YES IT WILL CRACK!!

I've seen many pics of permanently damaged CF seatposts from people who overtorqued them. The seatpost should have a recommended torque, follow it!

 

[Sprint2Win]

With some CF seatposts, you'll never reach the recommended torque, the seatpost will crush first. Tighten only enough to keep it from slipping.

Just wondering if it matters how hard you tighten a carbon fiber seatpost?
will it crack?

 

[gclark8]

Felt have a download page on CF torque settings: http://www.felt.de/felt/index.php?de_karbon_pflege
or
http://www.felt.de/felt/index.php?carbon_care_guide

 

[Walrus]

Just wondering if it matters how hard you tighten a carbon fiber seatpost?
will it crack?

The torque setting on a carbon seatpost is not as critical as that on a carbon stem or handlebar. The seatpost is not subjected to the same forces as a handlebar/stem (it has to hold your weight, not sustain pushing, pulling and twisting).

I've successfully adjusted my carbon seatpost after lengthy discussions with LBS mechanics. They said to just tighten it "tight"...not white knuckle, eye-popping tight...just tight.

If you want to play super-safe...fork out for a torque wrench.

 

[stea1thviper]

I would also add that with carbon fiber seatposts, there are different torque reccomendations for different brand carbon posts. most companies will have that information somewhere on their site. also +1 for a torque wrench.

 

[benkoostra]

Get a Ti post. And don't overtighten it!

 

[BikingBrian]

Something interesting about carbon posts that I have noticed:

I got my first carbon post almost 12 years ago, as I thought it looked cool, and I wanted something lighter than what I had (a Shimano 600 post)...Latido, a Japanese maker, very nice post, I tightened it just as I did any other post (I didn't know any better then)...but no problems at all. Since then, over the years I have also used Look Ergoposts and USE carbon posts....again no problems. Then, starting about 3 or 4 years ago, when a lot of carbon posts got lighter....ITM, Campy posts....even not tightening down very much, inevitably got crimped from the gap in the seat collar. It seems to me that probably quite a few companies started making their post walls thinner in order to save weight...and subsequently, they are too fragile.
In my opinion, not worth it to save a few measly grams....I got a Thomson about a year ago, and will never go back. Wonderful piece of aluminium engineering!

 

[badkarma]

I got a Thomson about a year ago, and will never go back. Wonderful piece of aluminium engineering!

I couldn't agree more. I picked up a Thomson elite seatpost a few months back and it's fantastic.

 

[caferacerwanabe]

More important than the torque is that you use a carbon friendly seatclamp, NEVER use a quick release seatclamp & for the really stupid among us never attach a kids tag-along bike to a carbon post & for that matter a superlight Alu one!
I read recently that FSA are making a special grease now for carbon parts.

 

[benkoostra]

I buoght an American Classic Ti post from a friend a few weeks ago. It's VERY light, and I'm not concerned about it breaking. Carbon is great, but it has limitations in certain applications.

 

[dhk2]

I couldn't agree more. I picked up a Thomson elite seatpost a few months back and it's fantastic.

+2 for the Thomson Elite. Lightweight is always nice, but not at the expense of strength or real-world durability. Besides, saving a few grams on a seatpost is nothing considering I carry 1500 grams of fluids on many rides....not to mention the extra grams on the body.