De Rosa BB scratches

cld531c

DeRosa2 by Claire Dwyer, on Flickr

De Rosa1 by Claire Dwyer, on Flickr

Does this look right to you? It looks like it has been scoured (only done about 20 miles!)
Thanks

fenix

What are we looking for ? Those marks on the metal of the outside of the BB ? I can't say I've ever looked that closely.
Nothing could be rubbing it as it rotates can it ?? Cos that would be wrong - but other than that...

veronese68

It looks a bit like what I'd expect after facing a threaded bottom bracket shell, but that doesn't look like it's threaded. Is the non-drive side the same? Can you see anything rubbing that would cause it?

Matthewfalle

Was it like that before the bb was fitted and/or immediately afterwards prior to the bike being ridden?

As V says, looks like facing marks but I don’t know whether that is a threaded/non threaded bb.

Any scraping/movement/etc when spinning the cranks by hand?

cld531c

Thanks for the responses.
I bought the bike fully built. I didnt really notice it at first as its not really a place you would look. The vendors responses have been

1. The bare metal that you can see is actually part of the BB shell that is bonded into the frame. This is perfectly normal to be able to visually see the lip of this extending from the bottom bracket shell.

This is the external lip of the shell that the press fit BB fits into to secure it into the frame and hold the chain set in place. I can confirm that this is how it is supposed to look from the factory and that this is perfectly safe to continue riding the bike.

and when I pointed out that it was the scratches and rough surface that concerned me (not the lack of paint)....

2.In this case the only way that this surface can become scratched is for the chain to drop off the 34t ring on your chain set and catch the edge of the BB shell on its way down. If this has happened while you have been on the bike then you would definitely know about it as you would have lost all drive and would have had to put the chain back on the ring to be able to ride again.

These BB shells do not come as a highly polished finished item like a chain or cassette. If the chain does drop off the 34t small ring, (which at some point during the bikes life probably will) then the leading face of the BB shell will be scratched instantly which is why they do not finish it. By Finish I meant sand and polish to a high luster.

This is perfectly normal, I have included a picture of a brand new De Rosa frame with the same BB set up that has the one you have which shows the unfinished effect as well.

I havent dropped the chain and am just concerned something may not have been set up properly. If it is just cosmetic then no biggie as i dont tend to look down there"!

EDIT Nothing seems to catch when spinning by hand but concerned that may be different when under pressure...

cld531c

And it has a 36 not a 34 which I would have thought they should know :-)

veronese68

In that case the honest answer would have been that they don't bother finishing that bit nicely as they don't expect people to look at it. If anything was rubbing enough to gouge the metal you'd feel and hear something.
If you want to be certain put a thin smear of something that you can wash off over the surface before you go for a ride. Look at it again after your ride and see if any of it has been rubbed off. If it look the same just wash it off. I'm almost certain it's fine though.

cld531c

Veronese68 wrote:

In that case the honest answer would have been that they don't bother finishing that bit nicely as they don't expect people to look at it. If anything was rubbing enough to gouge the metal you'd feel and hear something.
If you want to be certain put a thin smear of something that you can wash off over the surface before you go for a ride. Look at it again after your ride and see if any of it has been rubbed off. If it look the same just wash it off. I'm almost certain it's fine though.

Thanks - good idea
Thinking sudocrem would go nicely with the frame :-)

fenix

And double up if you get a sore bum.

imposter2.0

Still not sure what I'm supposed to be looking at. Everything I can see in the pics looks perfectly normal to me.

cld531c

Apparently all is well they just dont finish that area off properly cos they think no one will notice! Thanks again for the helpful replies

Matthewfalle

Any chance of pics of the whole bike for De Rosa nosiness purposes?

cld531c

Matthewfalle wrote:

Any chance of pics of the whole bike for De Rosa nosiness purposes?

De Rosa by Claire Dwyer, on Flickr

Of course....Since pic bars lowered, pedals and cages changed and saddlebag removed! (paving still grubby though!)

Matthewfalle

cld531c wrote:

Matthewfalle wrote:

Any chance of pics of the whole bike for De Rosa nosiness purposes?

De Rosa by Claire Dwyer, on Flickr

Of course....Since pic bars lowered, pedals and cages changed and saddlebag removed! (paving still grubby though!)

Very cool - hat.

You’ve gone the right way with the lowering/removal: it’s a De Rosa not some shonky Trek. Not designed to have junk all over it.

Top work!

veronese68

cld531c wrote:

(paving still grubby though!)

Got your priorities right then.

cld531c

Thank you- just need to get it off the turbo and on the road!