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Brompton carbon seatpost; any feedback?

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Brompton carbon seatpost; any feedback?

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Old 09-26-16, 04:40 PM
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ttakata73
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Brompton carbon seatpost; any feedback?

I saw one thread on the Litepro, but now Hylix has a carbon seatpost.
Anyone have either and have issues, or is it fine?

I have a carbon seatpost on my Dove and I can't stop it from rotating even after experimenting with carbon paste, aluminum shims, and duct tape.
If I clamp down on the tube too much the carbon will fail; in fact I heard a small crack as I was clamping it tighter.

I don't want another useless carbon seatpost but they are lighter than the titanium ones.
So anyone have success with a carbon seatpost on their Brompton?
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Old 09-26-16, 05:20 PM
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Originally Posted by ttakata73 View Post
I saw one thread on the Litepro, but now Hylix has a carbon seatpost.
Anyone have either and have issues, or is it fine?

I have a carbon seatpost on my Dove and I can't stop it from rotating even after experimenting with carbon paste, aluminum shims, and duct tape.
If I clamp down on the tube too much the carbon will fail; in fact I heard a small crack as I was clamping it tighter.

I don't want another useless carbon seatpost but they are lighter than the titanium ones.
So anyone have success with a carbon seatpost on their Brompton?
if it's cracked don't ride it.

what's the difference in weight between a 580mm carbon post and a titanium post?

a carbon seatpost that long and under butt and clamp load just doesn't seem like a good idea...

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Old 09-27-16, 10:49 AM
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I've got a carbon seatpost on my Brompton and it was fine with the stock seatpost clamp but slips slightly with an ultralight seatpost clamp.
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Old 09-27-16, 11:30 AM
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Originally Posted by leoho5 View Post
I've got a carbon seatpost on my Brompton and it was fine with the stock seatpost clamp but slips slightly with an ultralight seatpost clamp.
do you play stringed instruments?
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Old 09-29-16, 07:26 AM
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Originally Posted by smallwheeler View Post
do you play stringed instruments?
Rosin on the seatpost?
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Old 09-29-16, 01:53 PM
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RE; the slipping Not the carbon choice..



I modified* a QR Band clamp to grip the seat post itself to cure it slipping down.

Folding I open 2 levers one on top of the other

( B's Own Steel extended post , for my 220# )

* removed the top edge lip (which becomes the Bottom edge as I flip it over)




./.

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Old 09-29-16, 02:55 PM
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Originally Posted by smallwheeler View Post
if it's cracked don't ride it.

what's the difference in weight between a 580mm carbon post and a titanium post?

a carbon seatpost that long and under butt and clamp load just doesn't seem like a good idea...
What's the difference in weight between the carbon post and an aluminum post?
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Old 09-29-16, 04:17 PM
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What is the length and wall thickness of the 2 tubes you are trying to Compare?

Both 580?, then the wall thickness needs to be discovered ..
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Old 09-29-16, 06:21 PM
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Ebay says the Hylix carbon is 266g and the J&L ti is 345g.
Both have the carbon 2 bolt heads and are at 600mm length.
I guess I will keep bidding on the ti version since I have a Nov quick release and only want to deal with one QR.
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Old 01-12-18, 05:48 AM
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IVE been running the Hylix for a couple of weeks. It looks awesome and is very light BUT, itís very flexible. Iím switching out to a Kuosac Seatpost.

Hylix in my opinion:
Pros:
Looks awesome, light
Cons:
Doesnít have flange at bottom to stop the post coming out of the top and allow you to easily dial seatpost height, scratches up easily, way too much flex.
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Old 01-12-18, 02:47 PM
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you dont measure distances, thicknesses , with a gram scale do you?

if there were a whole additional layer or 2 , of carbon fabric added before the epoxy cured it would be stiffer...

may add a few grammes in the process...

a bit of DIY, you can add another couple layers inside the existing tube and bond it ,
the air pressure from a bladder hose can expand to push out air bubbles..





...

Last edited by fietsbob; 01-12-18 at 02:52 PM.
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