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Discussion Starter · #1 ·
Hello bicycle people

Just went out for a quick test spin on my new (almost complete) bike and the seatpost slipped down 25mm or so, didn't notice untill I got back so it must have been gradual.

Normally I would just give the seatpost clamp a bit of extra squeeze, but as I am using a carbon post I am a little worried about crushing the carbon walls

it's one of the new USE 'direct' fit carbon posts with thicker walls that do not require a shim - 31.6mm - going into a Klein attitude frame



Now my question.....

The little bit of info that came with the Klein frame states:

For seat post binder bolts, tighten to 85-125lb/in (9.6-14.1 nm)

Does anyone know if this torque setting is suitable for all kinds of post (steel, alloy and carbon ? )

I don't have a torque wrench, so might have to pay the LBS a visit.

Cheers for any info

Ty
 

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Is the position of your clamp in the photo your usual setup? I think you`ll find that if you move your clamp so that the bolt is over the frame cutaway it will be more affective in securing the post.
 

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Discussion Starter · #4 ·
top_ring said:
Is the position of your clamp in the photo your usual setup? I think you`ll find that if you move your clamp so that the bolt is over the frame cutaway it will be more affective in securing the post.
This is the sticker that comes with USE Carbon posts.
 

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Yes - it distributes the pressure more evenly but in my own experience this method was less effective. I too had the same problem but it was solved by having the bolt over the split in the seat tube. I would get some more advise and borrow a torque wrench if you can, just to eliminate that cause.
 

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Grease

top_ring said:
Yes - it distributes the pressure more evenly but in my own experience this method was less effective. I too had the same problem but it was solved by having the bolt over the split in the seat tube. I would get some more advise and borrow a torque wrench if you can, just to eliminate that cause.
For the 180 degree-solution to work well, I suggest using som heavy duty grease or copper paste between the clamp and the frame. When the clamp is turned, the clamp has to glide on the frame, and too much friction between the two will make it impossible to get any clamping force on the post.

Ole.
 

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The only way I have gotten carbon posts to stay put for any length of time are to:

1) Tighten the bolt enough to leave a permenant dent in the post.
2) Install to the correct height. Mark top of seat tube on post with tape. Remove post and use sand paper to lightly rough up finish directly under where it is clamped in the frame.
3) Sell the carbon post to some sucker and replace with a Thomson Masterpiece.

IMO, carbon is good for a lot of applications. Seat post tubes are not one of them.
 

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Discussion Starter · #9 ·
cheers for all the input everyone.


Has any here got a USE carbon post (the new thicker walled 'direct fit') and if so, what did you torque it too and where did you get this info ????


:confused:


Ty
 

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Discussion Starter · #10 ·
OK

Post below the seat clamp lightly sanded, just to take the gloss finish off.

Inside of seat tube cleaned with lighter fluid (Ronsonol).

Inside of seat tube and seat post covered in a 50/50 mix of chalk and talcum powder,

Seat clamp bolt given an extra half turn.



let's see what happens !


Ty
 
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