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I read 12Nm torque on my seatpost (a Cinelli Vai seatpost).

What does this torque refer to?

I would assume it's for the two bolts above that tie the saddle rail to the seatpost, but at the same time it looks like a very high torque to me for those bolts, so I am confused.

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I suggest looking at this table from Park Tool for what each component needs for torque.

For the seat rail binder (aka seat fixing bolt aka the bolts you've photographed), Park tool gives a range from 174 - 347 in-lbs as the Shimano value, with some others requiring as little as 44 or others as much as 300.

If we convert 174 in-lbs to N-m, thats about 20 N-m (the rule is divide by 9-ish). So, its a reasonable value for the bolts under question.

As noted in the table, the number doesn't really make sense for the seatpost binder (thing that holds the seatpost in the frame); you normally just go enough that it doesn't slip for that, which Campy suggests 4-6 N-m which is much lower.


All being said, I'm not sure who actually measures that torque unless you have fragile saddle rails or post or something. But I suspect many people go (well) below the 20 Nm ish figure from Park Tool by a good amount. I've never used a torque wrench for this, but I'd guess I've tightened with 10 Nm at best.

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    The rail bolts on my new bike say 10Nm so that sounds sensible (the label couldn't really apply to anything else on mine). Also the seat post clamp could be a long way away at maximum extension. – Chris H May 22 '17 at 20:49
  • Thank you very much for the answer, that table is a great resource! Compare to the values reported on the Park Tool chart, 12 N-m sounds too low now :) – Alessandro Cosentino May 22 '17 at 21:07
  • @AlessandroCosentino - well, its highly dependent on the type. The single bolts are obviously higher, but even for the standard variety, there is a wide range. – Batman May 22 '17 at 21:08
  • That's for the saddle rail bolt. The clamping of the post in the seat tube is usually in the range of 5-7Nm. – Carel May 23 '17 at 19:26

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