Too much torque?

[Oldgit]

A few months ago I upgraded the seat post that came on my Trek 7.3FX (had 2 bolts break on the original) with a Thomson Elite set back post. Before changing the post I had been experiencing an annoying click when riding for some time and this continued after changing the post. I've finally found the cause of the click: the seat post needed a bit more tightening and I had been riding with it at the max of 9 nm, however, I now have the post tightenened to 10.5 nm. By over-tightening the seat post clamp by 1.5 nm am I likely to cause any real damage to the frame?
Thanks in advance.

 

[Herzog]

Perhaps, but perhaps not - I wouldn't over-tighten if I were you. I suspect there will be a bit of leeway in the max stated torque...

 

[Oldgit]

Perhaps, but perhaps not - I wouldn't over-tighten if I were you. I suspect there will be a bit of leeway in the max stated torque...

Thanks Herzog but don't really have a choice in over-tightening as at the max setting of 9 nm the post 'clicks' in the frame. 10.5 nm was the minimum that got rid of the noise.

 

[dellzeqq]

this may be a case of trying to teach your grandma to suck eggs, but the only time that I've got clicking in seat posts is when, for reasons that are too embarrassing to go in to, I've been riding a frame that is a fraction too small and using a seat post that is too short - and, thus, the seat post is acting as a lever, and exerting too great a force on the frame.

Could this be the problem?

 

[Oldgit]

Thanks dellzegg, I can see the sense in what you say but think I have the right size frame: I'm a shortarse at 5' 6" and have a 28" inside leg, the frame is 17.5" and I have about 200mm of the seat post still inside the frame. Do you think the extra tightening will cause any damage?

 

[Sleeping Menace]

it's never a good idea to exceed a torque spec, especially when they clearly label with something like 'Max 9Nm'. If you're not able to get rid of creaking, groaning, or clicking at 9, then there's another problem.
is it likely to cause damage? it well may.. and the damage may not be immediately apparent. Excessive tightening increases the likelihood of a bolt breaking, or some part of the structure cracking.
Take out your post, clean it.. using an old coat hanger and a rag, clean out your seat mast.. put a very light flim of white grease on your seat post, and try tightening it to spec..
If this doesn't get rid of the clicking, then take it to your local shop to have them take a peek, but remember, the 'MAX rating.. is just that.. a maximum.. ie: it's best to snug it up to 7.5 or 8Nm first.. and see how it goes..

just my 2c.

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[albion]

Maybe the more expensive the frame the less the leeway but I always tighten to the GM.GM = guess mark.

 

[billy1561]

Interesting this as i asked my LBS today the same question. On the tube it states between 7-9 nm. I asked how i could measure this with an allen key and he said tighten until you feel it resist then just give it a quarter turn extra. Not very scientific but thats what he does he rekcons. With mine being carbon wrapped he said overtightening would crack it.