Hi all,

I recently bought a Rose SL 2000 pro bike which I have still not had the chance to ride. Just a few nights ago, as I was assembling the bike, I noticed that there are quite a lot of paint imperfections on the carbon forks, I myself could look past some of these because I think that a lot of bikes are plagued by this due to the process of painting carbon parts (I might be wrong, I am a newby), but what I saw next made me unsure if I just had a bad apple…
As you can see from the picture I have attached, on the bottom of the fork, you can see a clear dent where the wheel hub attaches.

Bearing in mind that I have only had this bike for about 5 days, do you think it’s worth sending this back and getting it exchanged?

What are your thoughts on the dent and the pain imperfections?

Thanks,
Ohms.

https://drive.google.com/file/d/0B-6Za_hDLx2mQ2VxT05JMno0QS1sRGNMdlNPUnN1Z3YzWFpj/view?usp=sharing

https://drive.google.com/file/d/0B-6Za_hDLx2menZ3Zml4SnpuM2lpM3d4SGxfaWNyUF96eXhr/view?usp=sharing

https://drive.google.com/file/d/0B-6Za_hDLx2mb3Z1U181eTlzWkJGRWhLVFA0LWFMV011c1Z3/view?usp=sharing

Edit: looks like the images didn’t work, so I switched them for links.

The “imperfections” are a natural result of the carbon layup process. There’s no paint.

That little “dent” (assuming I’m seeing what you’re referring to) looks fine too.

As Scotroutes said that’s not paint imperfections – that’s what carbon looks like if you don’t paint it. That’s a ‘raw’ UD carbon finish. Sometimes it’s painted with a grey paint to make it look tidier, sometimes not. It’s not a fault. As for the dimple (dent) I’d not worry about it. If you strip the paint of an alu bike there’s a good chance you’d find some filler covering over a small imperfection- carbon has the same but as the forks are raw there’s no hiding it. These are hand laid products prone to small imperfections. On a 10k bike they’d probably reject it. You bought a rose which is very good value, they can’t be quite so picky all the time.

Fin from Rose UK is a top bloke… drop him a line if you are worried – I think any emails for Rose UK go through to him anyway.

Perfectly normal, moulding witness marks and decals applied over bare UD finish.

What they all said.

Thanks everyone for the quick replies, much appreciated.
Yea I agree with dovebiker that the marks seem to be only around the stickers, with some shiny spots (probably poorly applied clear coat) dotted around the forks.
I was just worried that come time to sell the thing, I would get comments about this stuff..
Those are definitely not moulding witness marks tho (unless the mould is of poor quality). 🙂

i had a rapide rl2 disc which had a faulty carbon fork which resulted in me hitting the ground pretty hardonly had it 2 months and was only its second ride out..

I am also worried about that. A notch like that, even though it appears small, can significantly impact the performance of a weight bearing component like that.

hms93 – Member
I am also worried about that. A notch like that, even though it appears small, can significantly impact the performance of a weight bearing component like that.

MWAHAHAHAHAHAHAHAHAHAHAHAAA – you’d better not look at my carbon forks then.

Keep an eye on it to see it’s growing but I wouldn’t give it a second thought.

You wouldn’t be laughing if you studied fracture mechanics in a mechanical engineering course. A notch just 1 micrometer deep can increase the stress concentration significantly in a load bearing parts even causing it to fail prematurely. Usually the size of a notch increases the stress by a^0.5 where a is the notch size. In lab testing to measure fracture toughness of a material, we induce notches in increments of 1 micrometer thickness.
I am not saying that what I have is a notch on a weight bearing section, but it’s something for me to keep an eye on.

Ohms, I would say that your knowledge of fracture mechanics is probably why your a bit more worried than an “average”rider might be.

I recently got my first (second hand) carbon fame and was very precious about it at first to be honest. I noted every tiny imperfection and got all concerned about it. After having ridden it many times now I just don’t worry about it anymore. I do use a torque wrench now but that’s the only change really.

Carbon is really rather nice actually and a lot harder than I thought it might be.

Enjoy the new bike mate! 🙂

If forks were built such that a 0.5mm imperfection on a brand new pair caused failure then there would be a lot of dead cyclists.

Those marks are the carbon, it’s not the clear coat.

Poopscoop, you are probably right mate, I think I am worrying myself. Thanks!

njee20, I am not saying that it will immediately cause a fracture, I am saying that notches reduce the yield strength of a material. So basically a notched frame is a weaker frame (or one that is more likely to fail earlier and has a shorter life span). I am closer to the 100kg limit that probably a lot of you here though, so I worry a little more. 🙂

Ohms, I’m pretty much spot on 100kg at the moment too. 😉