Carbon steerer scratch / gouge

buder

Hi all,

Recently got a new Orbea Orca and needed to adjust headset. I noticed the expander bung had slipped a bit so took the stem off and spacers etc and spotted the mark directly situated under the lower left stem relief.

It has not been overtightened and always had a torque wrench used to 4.5nm. I would have thought if it had been overtightened you would see both stem reliefs imprinted etc so for it just to be one side of the lower stem relief it seems odd. Possibly due to a sharper edge on that side of the stem perhaps.

You can run your finger along it doesn't feel sharp in anyway but it goes into the resin on the top layer if thats what it is ?

The bung extends to 70mm so a further 20mm beyond the mark in the picture.

What are peoples thoughts on this mark ?, its not cracked nothing can be felt on the inside either but its making me nervous.

[url][/url]IMG_1843 by 7e2ca155e724efbf4147f41dda72eb2c, on Flickr

ryan_w-2

Remove FSA 20mm spacer, slam stem, cut off excess. Problem solved.

That would not worry me one bit.

svetty

If there is a really sharp edge on the stem I might gently smooth this off a touch on the inside but other than that I wouldn't worry about this at all.

buder

Ryan_W wrote:

Remove FSA 20mm spacer, slam stem, cut off excess. Problem solved.

That would not worry me one bit.

Hiya - didn’t think of that tbh, if I did slam the stem the top stem relief would be over the area in question so not sure it would make much difference.

I could remove one of my spacers and have the gouged area in the middle between the stem bolts ?

svetty

buder wrote:

Ryan_W wrote:

Remove FSA 20mm spacer, slam stem, cut off excess. Problem solved.

That would not worry me one bit.

Hiya - didn’t think of that tbh, if I did slam the stem the top stem relief would be over the area in question so not sure it would make much difference.

I could remove one of my spacers and have the gouged area in the middle between the stem bolts ?

This seems a strange way forward - assuming the stem is currently set so that the bike fit is correct why compromise your fit? Of course if you could easily accommodate a lower front end then go for it - and enjoy better aero position

bobones

It looks fairly insignificant to me, and I would not worry about this at all, particularly as the bung is supporting the steerer tube against the clamping forces of the stem at this point.

lesfirth

That is nothing to worry about at all. The steerer is incredibly strong. If you have doubts go to your LBS and ask if they have a bit of carbon steerer they have cut off. Take it home and try to destroy it. I think you will be surprised.

buder

Svetty wrote:

buder wrote:

Ryan_W wrote:

Remove FSA 20mm spacer, slam stem, cut off excess. Problem solved.

That would not worry me one bit.

Hiya - didn’t think of that tbh, if I did slam the stem the top stem relief would be over the area in question so not sure it would make much difference.

I could remove one of my spacers and have the gouged area in the middle between the stem bolts ?

This seems a strange way forward - assuming the stem is currently set so that the bike fit is correct why compromise your fit? Of course if you could easily accommodate a lower front end then go for it - and enjoy better aero position

It would be a case of having to compromise over the safety of the steerer if that’s in question.

The gouge it fairly significant when you run your finger over it, definitely not a crack tho.

I’m just concerned it could be a stress riser leading to a crack or delamination etc.

My biggest fear on the bike is the bloody bars coming off !!.

lesfirth

"I’m just concerned it could be a stress riser leading to a crack or delamination etc."

.[/quote]

If you have the expertise and knowledge of carbon fibre construction to make statements like that there is no point in asking opinions on this forum,which you then choose to ignore.
I do not have that knowledge ,perhaps you could explain what a "stress riser" is.

mamba80

buder wrote:

My biggest fear on the bike is the bloody bars coming off !!.

It would happen so quickly you wouldnt have time to experience fear........

all you ve done is left an imprint in the surface decorative carbon layer, did same thing on a carbon steerer several years ago, 1000's of miles and years later, i am still here.

if it really bothers you, check the steerer every now an again until you forget all about.

The Rookie

A little dent in the matrix (plastic/resin/PEEK) material is neither going to cause a meaningful stress raiser nor weaken in in any meaningful way. I really wouldn't worry about it at all, I wouldn't compromise the ride position either, although if you slammed and flipped the stem the bars would be pretty much back in the same place if you wanted to do that.

Third year project was on CF plates for the USAF back in 1988.

buder

lesfirth wrote:

"I’m just concerned it could be a stress riser leading to a crack or delamination etc."

.

If you have the expertise and knowledge of carbon fibre construction to make statements like that there is no point in asking opinions on this forum,which you then choose to ignore.
I do not have that knowledge ,perhaps you could explain what a "stress riser" is.[/quote]


Not sure I chose to ignore anyones comments.

If I had the "expertise" then I wouldn't need to gauge opinion on what is/was something that caused me some worry and concern.

With things of this nature it tends to divide opinion, most shops will always stay on the side of caution so this is why the forums are great because you tend to get an honest unbiased opinion.

I will certainly keep my eye on it, some peoples view is that you don't get a mark on a steerer unless its been overtightened and in that case its compromised.

I appreciate all the comments, depending on the consensus I was going to swap the forks but now I will leave them and monitor once a month or something.