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I have an On-One Scandal aluminium frame, into which i have put a carbon seatpost. I have been adjusting it to find the right height, and i have noticed that it is getting seriously scratched - see a terrible photo. The scratching isn't deep enough to weaken the seatpost, but it looks ugly.

I have tracked some of the scratching down to the sharp edge around the top of the seat tube, and around the clamp notch (or whatever you call that). I have filed those so that they are smoothly chamfered, and now they don't scratch the seatpost.

However, further down the seat tube, the top tube and seatstay trunk (or whatever you call that - on this frame, the seatstays don't join the seat tube directly, they join on to a short piece of fat tube which then joins the seat tube) join on. Where each joins, there is a small hole in the wall of the seat tube (i suppose these are to ventilate the insides of their respective tubes). These holes have sharp edges, and i believe it is these which are scratching the seatpost.

Has anyone else come across this problem?

The holes are too far down to be able to get a file at them. I've applied some carbon assembly paste around them, and that helps a little (it seems to act as a lubricant when not clamped).

How can i stop my seatpost getting scratched?

share|improve this question
I don't think I've ever seen a seatpost that wasn't scratched. – Daniel R Hicks Apr 14 '13 at 23:41
But mine is SO BEAUTIFUL! – Tom Anderson Apr 15 '13 at 0:12
@Tom: Correct tense here is "was" :( – mattnz Apr 15 '13 at 3:20
I just tried my smooth,shinny mountain bike seat post in my road bike and if scratched it up so ugly and both posts are the same damn thing. :( i know this is caused by the seat tube. – user8879 Dec 27 '13 at 15:31

Possible solutions:
- Let a bike mechanic ream the seat tube slightly
- Wrap some sanding paper around a broomstick or similar an grind the sharp edges

share|improve this answer
+1 for the sanding paper, looks like a solution that might work. – Uooo Apr 15 '13 at 12:43

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