Road Bike, Cycling Forums banner
1 - 13 of 13 Posts

·
Registered
Joined
·
171 Posts
Discussion Starter · #1 ·
I got my first carbon seatpost ever - a Campagnolo - read the instructions, installed it. And of course I did scratch it in the process all the way from bottom to clamp height. Campag manual wants me to believe my seatpost is now an accident waiting to happen, is this so?

Has anyone here ever actually ruined a carbon seatpost by simply scratching its surface? How easily is this accomplished (ruining it, not scratching)? I think I only managed to scratch the lacquer on the surface, but then again can't be absolutely sure. I did sandpaper the frame so there shouldn't be any large metal chunks digging themselves into the post.

Also what should I make of a nasty sound like sand being ground when I tighten the clamp bolt? Not exactly what I wanna hear. I'm pretty sure this noise comes from the bolt and not the seatpost so I guess it's just one of those things. How loose can the clamp bolt be left for it to still be safe? I haven't done it to max torque because the noise starts around 0.8k and max torque is 1.0
 

·
Registered
Joined
·
171 Posts
Discussion Starter · #3 ·
Dave Hickey said:
I wouldn't worry about the scratch as much as the sound it makes when you tighten the clamp. The "sandpaper" sound sure sounds like the post being crushed....
I certainly hope I haven't crushed it. It did sound awful but the noise is gone now (don't know if this is a good thing or not) and I even tightened it a bit more. There's no grinding/creaking sounds when I sit in the saddle, so I hope it didn't come from the post rather some dirt on the bolt or something like that. Too bad I can't test ride the bike for another month or two... ice and snow everywhere here.
 

·
Diesel Engine
Joined
·
898 Posts
schimanski said:
I certainly hope I haven't crushed it. It did sound awful but the noise is gone now (don't know if this is a good thing or not) and I even tightened it a bit more. There's no grinding/creaking sounds when I sit in the saddle, so I hope it didn't come from the post rather some dirt on the bolt or something like that. Too bad I can't test ride the bike for another month or two... ice and snow everywhere here.
Since you can't ride it, take out the post and inspect the 'scratch' to see how deep it really is. Find out the source and eliminate it. While the post is out, retighten the seat tube clamp. If the noise is still there, clean and lube the bolt and possibly the clamp (there may be dirt between the clamp and the frame. If it is silent, I'd inspect the area on the post where the seat tube clamp made contact a little closer.

If your bike has a separate clamp (not part of the frame but it slips over the seat tube, make ABSOLUTELY sure that this clamp is not touching the post when you tighten the bolt. This will be bad. There should always be a gap between the clamp and the post. I worked on a friend's bike not too long ago where the clamp was not all the way down on the seat tube and was overtightened - he had a nicely crimped post that needed to be replaced. With carbon the force would surely damage the post at least this much.

Good luck.
 

·
Registered
Joined
·
2,601 Posts
I haven't touched it for a while, but I faintly remember the bolt containing some sort of hard dried thread lock material which may have caused the grinding sound.
 

·
Registered
Joined
·
171 Posts
Discussion Starter · #6 ·
divve said:
I haven't touched it for a while, but I faintly remember the bolt containing some sort of hard dried thread lock material which may have caused the grinding sound.
That could explain why it didn't make the noise after I'd loosened the bolt a couple of times while adjusting to correct height. Also if there's something like that in the bolt/clamp could this explain why it shouldn't be lubed?
 

·
Registered
Joined
·
171 Posts
Discussion Starter · #7 ·
Mike Prince said:
Since you can't ride it, take out the post and inspect the 'scratch' to see how deep it really is. Find out the source and eliminate it. While the post is out, retighten the seat tube clamp. If the noise is still there, clean and lube the bolt and possibly the clamp (there may be dirt between the clamp and the frame. If it is silent, I'd inspect the area on the post where the seat tube clamp made contact a little closer.

If your bike has a separate clamp (not part of the frame but it slips over the seat tube, make ABSOLUTELY sure that this clamp is not touching the post when you tighten the bolt. This will be bad. There should always be a gap between the clamp and the post. I worked on a friend's bike not too long ago where the clamp was not all the way down on the seat tube and was overtightened - he had a nicely crimped post that needed to be replaced. With carbon the force would surely damage the post at least this much.

Good luck.
I couldn't feel any bumps or sharp edges in the seat tube but sanded it anyway. The seatpost did not get more scratches to the side where I'd scratched it before so I guess I took out whatever there was. It looks like it's scratched on the surface only. I can't see any fibres sticking out or anything that much alarming. But I don't have a magnifying glass or any other way of knowing for sure.

Lubing the bolt and clamp? These two are especially forbidden in the Campagnolo manual. I would have lubed the bolt in the first place but didn't think it would be a good idea when the manufacturer tells me I shouldn't. No explanation why it's forbidden, but there's a strict warning against it.
 

·
Registered
Joined
·
1,380 Posts
Carbon seat post experiences

My first Campy seat post was the Chorus Ti model. Never had a problem other than the bike was stolen!

So using the insurance money I built up a new bike, this time using a Record carbon seat post - looks like the same clamp as the Ti version. This new seat post has been a major pain ever since I bought it. First off it creaks from the saddle clamp area. I don't understand why this seatpost should creak since the clamp is identical to the Chorus version which never gave me any trouble. I even tried a new saddle to make sure this wasn't the problem. Next the seat post stuck in the frame: clear paint stuck fast in the seat tube and took a significant amount of force to get it out. Good news is that the carbon/epoxy seems just fine. In fact, I scraped off the clear paint to make sure the epoxy coat was not damaged - this is the important thing, not the clear paint.

So now I have an expensive seat post which creaks everytime I use it. That is, when I use it. Right now it's sitting in the "spares" box, i.e. "part hell".


Major waste of money.

Ed
 

·
Registered
Joined
·
9,079 Posts
Chorus Ti

Nessism said:
My first Campy seat post was the Chorus Ti model. Never had a problem other than the bike was stolen!

So using the insurance money I built up a new bike, this time using a Record carbon seat post - looks like the same clamp as the Ti version. This new seat post has been a major pain ever since I bought it. First off it creaks from the saddle clamp area. I don't understand why this seatpost should creak since the clamp is identical to the Chorus version which never gave me any trouble. I even tried a new saddle to make sure this wasn't the problem. Next the seat post stuck in the frame: clear paint stuck fast in the seat tube and took a significant amount of force to get it out. Good news is that the carbon/epoxy seems just fine. In fact, I scraped off the clear paint to make sure the epoxy coat was not damaged - this is the important thing, not the clear paint.

So now I have an expensive seat post which creaks everytime I use it. That is, when I use it. Right now it's sitting in the "spares" box, i.e. "part hell".


Major waste of money.

Ed
The Chorus Ti seatpost is much better than the Record, anyway, in my opinion. It may be the best looking seatpost ever made, except for maybe some old fluted pantographed work of art. But, alas, Chorus has gone carbon, too. Carbon just doesn't have the artsey feel of finely polished metal, does it?
 

·
Registered
Joined
·
171 Posts
Discussion Starter · #10 ·
Nessism said:
Next the seat post stuck in the frame: clear paint stuck fast in the seat tube and took a significant amount of force to get it out. Good news is that the carbon/epoxy seems just fine. In fact, I scraped off the clear paint to make sure the epoxy coat was not damaged - this is the important thing, not the clear paint.

Major waste of money.

Ed
Took the seat post out again today. It already had begun getting stuck in the frame. WTF. The paint/lacquer/whatever on the surface of the seat post has sort of "melted" from the clamp area and I can see it getting stuck there in the future. There might also be a slight crack in the carbon or maybe just a scratch, I don't know.. could be either one by the looks of it.

Next time I'll go for a titanium seat post for sure, this crap ain't worth all the trouble.
 

·
Registered
Joined
·
9,079 Posts
schimanski said:
Took the seat post out again today. It already had begun getting stuck in the frame. WTF. The paint/lacquer/whatever on the surface of the seat post has sort of "melted" from the clamp area and I can see it getting stuck there in the future. There might also be a slight crack in the carbon or maybe just a scratch, I don't know.. could be either one by the looks of it.

Next time I'll go for a titanium seat post for sure, this crap ain't worth all the trouble.
Some carbon posts have no coating. I know my USE Alien does not, and never had any getting stuck problems. I can't recall for certain, but I think my Colnago carbon post in my C40 did not, either; in any event, it never got stuck. That's fairly useless info, though, because I think the Colnago post diameter (28 something?) is unique to Colnago bikes.

Doug
 

·
Registered
Joined
·
171 Posts
Discussion Starter · #12 ·
DougSloan said:
Some carbon posts have no coating. I know my USE Alien does not, and never had any getting stuck problems. I can't recall for certain, but I think my Colnago carbon post in my C40 did not, either; in any event, it never got stuck. That's fairly useless info, though, because I think the Colnago post diameter (28 something?) is unique to Colnago bikes.

Doug
There is a coating on this one for sure. I'll see if the seat post gets stuck for good or if it fails on me. I don't think I'll be removing it before it's served its time. It does look rather nice though compared to my old, scratched and heavy aluminium monster... then again this may be the only positive thing I can say about this particular Campagnolo product so far. ;)
 

·
Registered
Joined
·
286 Posts
I scratched the crap out of mine when I installed it and that was nearly 2 years ago. I've never had a problem with the post at all and I weigh 215 lbs. (I was 237 when I got the bike) I haven't tried to take the post out since it was installed. I don't see any need to ever do so since it fits perfect. I'd recommend that you install the post and after you properly torque the clamp just forget about it.
 
1 - 13 of 13 Posts
Top