How much torque on a saddle with carbon rails?

[GhostRider2]

Hi Hubbers

 

Just bought a Selle San Marco saddle with carbon rails.

 

I'd like to install it but am a little nervous regarding how much torque to apply to the bolt.

 

My seat post is an FSA team issue with a single bolt.

 

There is no indication on the saddle and gooogle is giving me mixed answers to this.

[openmind]

Those carbon rails are tough - just snug it up hand-tight enough to stop it slipping. Take a tool with you on the first few rides in case it slips.

[Donovan Le Cok]

I had the same problem with the San Marco Superleggera, it also has carbon rails.

 

I searched the web and even wrote to San Marco, I never got a reply, I only get their news letter once a month now...

 

The only good piece of advice I got was from my LBS who said that I should tighten it to the torque spec of the seat post, that info should be easily available.

 

I found that if the rails aren't tight enough the saddle moves forward or back really easily, so you really have to tighten them a lot.

 

I have since managed to crack one rail, from riding though, not from tightening. I still use the saddle, but keep an eye on them.

Edited August 7, 2013 by NitroDoni41

[Butterbean]

Why don't you also try some carbon assembly paste? It'll let you torque just a bit less, and still hold the rails nicely. I used it on my old seat post that never really gripped nicely. Worth a shot?

[Vetseun]

Im not the torque wrench type. I hand tighten on feel. I have been known to break a few bolts in my time. I wouldnt take my advice.

[Thomo]

Small carbon bits (stems, saddle posts etc) seem to have similar torque specs.

Generally between 5 and 8 nm.

Start at the lower end of scale and adjust accordingly ... 6nm should however do the trick.

[David Marshall]

Tighten to the spec for the seatpost. Two bolt types are usually around 8nm. Single bolt ones are higher 10-15 nm. I would start at 10.

[Cylon]

I have a similar setup (carbon seat post & carbon rails) but with two bolts and each bolt is tightened at 7nm.

 

As Chowder says the single bolt types can go a little higher but I wouldn't go over 10nm.

 

[LOOK695]

My seat post says 22nm. Have a Fizik with carbon rails and have torqued it 16nm. If I go lower, I find that it slides backwards over time.

[Thomo]

My seat post says 22nm. Have a Fizik with carbon rails and have torqued it 16nm. If I go lower, I find that it slides backwards over time.

 

 

22nm.?

 

That sounds like plenty torque ...

[Jaco-fiets]

 

 

22nm.?

 

That sounds like plenty torque ...

 

Jeez! I will snap my wrench never mind the rails. I torque my seatpost at 6nm and I have to grid my teeth and close my eye. I hate that noise of snapping carbon

[VeloErv]

Got to make sure that your seatpost can take the oval rails of the seat first

[LOOK695]

22nm.?

 

That sounds like plenty torque ...

Jeez! I will snap my wrench never mind the rails. I torque my seatpost at 6nm and I have to grid my teeth and close my eye. I hate that noise of snapping carbon

Here is a pic of the EPost