seatpost slipping: suggestions?

[mike p]

Ck your seat post, not uncommon for them to be under and oversized.

I see this all the time and it always looks like such a engineering band-aid especially on a high end bike!

"one option, adam hansen uses a second seat collar. thoughts?"

[oliver1850]

I would measure the post and look for a slightly bigger one if the paste doesn't work. They can vary quite a bit with the same nominal size.

Another option is the double clamp if the frame uses a collar. Origin8 sold them, they clamp on the frame and the post.

http://www.ebay.com/itm/Origin-8-CLA...item4abbcc31ec

[Anarchist]

A beer can shim on the inside of the post works really well.

Have one on my Pegoretti for years now.

[linger]

Buy a thomson seat clamp.

[victoryfactory]

Assuming the sizes are all good and the bolt is not bottoming out
as mentioned by Peter, clean all the grease out and surface the inside
of the clamp/seat tube with sandpaper. That works for me cause you don't have to
do anything to the post itself.

VF

ps: try every one of these fixes and let us know the results. It shouldn't
take more than 6 or 8 months!

[Climb01742]

Partial update: I tried a different seatpost and it slipped too. My next two steps are to buy some calipers to confirm that the seat tube is, as appears, larger than stated and track down some Tacx carbon assembly paste. Fingers crossed. Frustrating.

And thank you everyone for all of your suggestions. The help is very appreciated.

[azrider]

Originally Posted by Climb01742

Partial update: I tried a different seatpost and it slipped too. My next two steps are to buy some calipers to confirm that the seat tube is, as appears, larger than stated and track down some Tacx carbon assembly paste. Fingers crossed. Frustrating.

And thank you everyone for all of your suggestions. The help is very appreciated.

Hey Climb.....what ever ended up happening with your slippage issue?

I'm obviously bumping because I'm having same issue with my CSI.

[oldpotatoe]

Originally Posted by azrider

Hey Climb.....what ever ended up happening with your slippage issue?

I'm obviously bumping because I'm having same issue with my CSI.

Find a decent lbs that has a knurling tool, knurl it dear liazza, knurl it.

[azrider]

Originally Posted by oldpotatoe

Find a decent lbs that has a knurling tool, knurl it dear liazza, knurl it.

Thanks for chiming in here OP. Unfortunately, the post I have is already knurled (that a word?) so that aint an option.

Background: I over-tightened seatpost bolt and broke it off in the seatpost cluster and had to have it backed out.

My shop lubbed it up really well and put stainless steel screw in there and now I'm too much of a wuss to tighten it too much. So i took it BACK to the shop and they tightened it down to "little more than 7Nm" and sure as sh*t it slipped about 2mm after 2 hour ride last night.

Can steel stretch over time ??

[Black Dog]

Originally Posted by azrider

Thanks for chiming in here OP. Unfortunately, the post I have is already knurled (that a word?) so that aint an option.

Background: I over-tightened seatpost bolt and broke it off in the seatpost cluster and had to have it backed out.

My shop lubbed it up really well and put stainless steel screw in there and now I'm too much of a wuss to tighten it too much. So i took it BACK to the shop and they tightened it down to "little more than 7Nm" and sure as sh*t it slipped about 2mm after 2 hour ride last night.

Can steel stretch over time ??

Yes. Steel is ductile. Try some carbon paste or drink a beer from a can and make a shim. Pop cans (Soda/Cola for my American Cousins) work well too.

[oldpotatoe]

Originally Posted by azrider

Thanks for chiming in here OP. Unfortunately, the post I have is already knurled (that a word?) so that aint an option.

Background: I over-tightened seatpost bolt and broke it off in the seatpost cluster and had to have it backed out.

My shop lubbed it up really well and put stainless steel screw in there and now I'm too much of a wuss to tighten it too much. So i took it BACK to the shop and they tightened it down to "little more than 7Nm" and sure as sh*t it slipped about 2mm after 2 hour ride last night.

Can steel stretch over time ??

Yes it can and the SP may be undersized to boot...if it still slips after being knurled.

[azrider]

Originally Posted by oldpotatoe

Yes it can and the SP may be undersized to boot...if it still slips after being knurled.

Well the post came knurled from factory so it wasn't done by shop.

I think next steps are to wipe down and clean off grease, put some grit paste in there, and buy a torque wrench

if that doesn't work i spose i could try the beer can shim

[oldpotatoe]

Originally Posted by azrider

Well the post came knurled from factory so it wasn't done by shop.

I think next steps are to wipe down and clean off grease, put some grit paste in there, and buy a torque wrench

if that doesn't work i spose i could try the beer can shim

Is it knurled or just couple of lines showing limit line? Being ‘knurled’ by shop is pretty aggressive and much deeper.

[azrider]

Originally Posted by oldpotatoe

Is it knurled or just couple of lines showing limit line? Being ‘knurled’ by shop is pretty aggressive and much deeper.

Guessing mine is more......ribbed than knurled




Sent from my iPhone using Tapatalk

[oldpotatoe]

Originally Posted by azrider

Guessing mine is more......ribbed than knurled




Sent from my iPhone using Tapatalk

Whomever ribbed it, may have made it smaller as well...I think a smooth SP, then knurled, would fix you up.