Saddle Slippage on One-bolt Chorus Carbon

[Spinner]

I have a Chorus Carbon Seat Post that has a one-bolt saddle clamp. My saddle slips regularly, typically after a bump in the road. It makes quite a screech when the splines in the cradle component rub past one another.

This Chorus post is mounted on my Rambouillet, which is primarily used for periodic multi-day tours. Before my last trip, I disassembled the seat clamp, cleaned everything thoroughly and then applied two drops of LocTite on the splines before tightening the bolt to a highly-wrenched degree of tightness (I don't have a torque wrench).

Is this post toast? What, if anything can I do to make it work?

Was thinking about a Nitto S-83 as a replacement. Other recommendations?

[Jeff N.]

Dab a little Gorilla glue on the clamp area, heavy grease on the bolt threads, and re-tighten. Voila! If that doesn't work, I happen to have a new clamp assembly for your Campy post. $20 get's it in the mail to you. -Jeff

[Hindmost]

Hummm? The spline design was pretty slip proof. The posts were made with different splines, initially course and then later fine. Could you have a mismatched post and post cap?

(Maybe we need to know what seatpost you have.)

[Spaghetti Legs]

The C Record era single bolt clamps, which I think might be the same style as yours, can have this problem. I don’t think the Loctite is giving you much help there as it is made for threaded surfaces. For me, lubing the bolt, as noted above and using a longer Allen wrench to super torque the bolt down tends to work. On one occasion I think I put rubber cement on the surfaces. Some people will lightly score the clamp surface with a file.

[Dave]

I prefer posts that use a 2-bolt rocker style clamp that allows very small changes to the saddle angle. The FSA K-force is the only one I've used for many years. You can get setbacks of zero, 25mm or 32mm.

I found a new one on E-bay for $110.


https://shop.fullspeedahead.com/en/type/seatpost?discipline=378

[Black Dog]

Pics?

[Spinner]

I'm late in responding, however I wanted to pass the word that this suggestion worked. This post has now withstood several hundred miles with no slippage whatsoever.

Thanks Jeff and cheers to all here who help with issues.

Dab a little Gorilla glue on the clamp area, heavy grease on the bolt threads, and re-tighten. Voila! If that doesn't work, I happen to have a new clamp assembly for your Campy post. $20 get's it in the mail to you. -Jeff

[Jeff N.]

Terrific!

[robt57]

Like this Gorilla glue?

https://images-na.ssl-images-amazon.com/images/I/81geyhHHd4S._SY445_.jpg

[Jeff N.]

Like this Gorilla glue?

https://images-na.ssl-images-amazon.com/images/I/81geyhHHd4S._SY445_.jpgThat's the stuff.

[Spinner]

That's the glue.

I was hesitant to post about the success of the fix until sufficient miles were ridden. I'm now confident that the clamp is firmly fixed.

Cheers.

[fmradio516]

That's the glue.

I was hesitant to post about the success of the fix until sufficient miles were ridden. I'm now confident that the clamp is firmly fixed.

Cheers.

did you need to wet the surface first? or just dab the glue on?

[Spinner]

did you need to wet the surface first? or just dab the glue on?

I thoroughly cleaned the splined surfaces and then spread a small amount of glue on both surfaces using a new flux brush.

[Hindmost]

Is everyone talking about the seat post with the splined head and cradle? In my experience the splines engage super-well and never slip.

(I first thought the issue was the saddle tipping in the cradle; I think you're talking about the rails sliding backward, still kind of unusual.)

[Spinner]

Is everyone talking about the seat post with the splined head and cradle? In my experience the splines engage super-well and never slip.

That's the one. I wish that mine hadn't slipped, but it did, on two multi-day trips. That was very problematic.

[RoosterCogset]

Isn't the usual first recommendation to just smear a bit of assembly compound on the clamp where it's clamping the saddle's rails?

[Spinner]

Isn't the usual first recommendation to just smear a bit of assembly compound on the clamp where it's clamping the saddle's rails?

Wish I had known about this stuff. Likely would have precluded the issue.

[ultraman6970]

Carbon fiber assembly paste thing.