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Hi
Am on the verge of a purchase of a second hand on-one c456 frame
Apart from the usual signs of abuse etc, what should I look out for on a 2nd hand carbon Mtb frame ?
The seller has openly just let me know that when the headset was installed, by a professional bike shop, a couple of very small cracks appeared in the laquer near the bottom cup.
He was told that this is common with the carbon construction when the headtube expands slightly on headset installation. There has never been any change in these during the sellers use of the bike.
Should this be cause for concern ?
Asking here as I have no experience with carbon frames whatsoever, thanks.
Normal or normal for on one? How cheap is used vs new?
£125 vs £350 or so
And normal for all I guess
They take a battering, should be fine. Most of what is likely to cause a failure you might not see so just look for big chunks out of it or creaking noises from the frame. Generalising here but most riders who've had this kind of bike are likely to be passionate about mountainbiking so perhaps a lower propensity for people to be trying to flog on a pup.
my two pence.
The paint on carbon frames can be thick and brittle so you get witness cracks where they flex. I think that's why manufacturers are using thinner matt paints now. This crack was on my carbon Roubaix for about 5000 miles and it didn't grow at all:
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456's are pretty overbuilt so it should be fine*. Just look for the usual signs of dings, dents, paint flaking or cracks (top of seat tube is a pretty common general one)
* unless it all ends horribly
Not bikes, but boats, this it the kind of mess you get in composites after 20+ years of abuse (my dinghy looks this bad in places and is much newer than that!). Doesn't affect their strength it's just the gelcoat is much more brittle than the material underneath.
this made me laugh !* unless it all ends horribly
Thisisnotaspoon - thanks for that !
globalti : that 'crack' looks worse than it is - obviously. Good to know it's likely to just be only surface deep.
The c456 is reputed to be a tough frame, I'm just being overly cautious - with no prior experience of carbon frames.