Drop out damage...

type_grim

Hi there,

I have had my new bike for about five weeks now, and have had no problems.

I gave it its weekly clean yesterday, only to find that somehow, the chain has tried to drop between the smallest cassette sprocket and the frame.

It appears to have flaked off the paint, and worn a smidgen of the aluminum drop out away.

It all appears cosmetic.

I take it that the rear mech is trying to pull the chain too far over? The rear mech is a Sram X-0 running with X-0 shifters.

I have spoken to the shop that i bought it from and they said to bring it in for its first service and they will take a look at it.

Where do i stand in terms of the damage, are the shop partly to blame or?

I really don't think the mark is terminal, it just needs touching up, but when you go spending 3k on a bike, it's not something i would have liked to have happened!

Other than having the rear derailleur adjusted, is there anything out there that can put put between the frame and smallest cassette sprocket, to stop this kind of damage?

Luckily, the drop outs are aluminum, and the rest of the frame is carbon.

Also, i have put the bike into the offending gear, and using all three chain rings up front, it doesn't appear to touch the frame.

G

The Northern Monkey

Possibly means that the stops weren't set up correctly on the bike in the first place... but then it would have happened more than once.

What bike is it?

type_grim

It's a 2009 Specialized Stumpjumper Marathon Carbon.

It has a Sram X-0 rear mech, XT Cassette, Sram PC-971 chain and an XT crank.

I can't say i have noticed a rubbing noise of any sort?

I guess i'm just lucky that i caught it before it did some serious damage.

I have booked it in this weekend, for its first free service and i have mentioned the graunch mark.

They said they will 'take a look at it'.

If it is the case, that the stops weren't set correctly, does that put the ball in their court, in terms of sorting the problem?

I can't think of any way how i could have damaged it myself?

I really do look after it (it bloomin cost enough!), so it's not through any form of neglect, nor have i fiddled with any drive train screws etc.

G

The Northern Monkey

not really tbh... I wouldn't be expecting a new frame if thats what you mean.

Got any pictures?

type_grim

Not yet no.

I think it sounds worse than it is! It's just annoying. I'll just have to touch it in with some black nail varnish or something.

I guess they will just adjust everything to stop it happening again.

I shall keep you posted.

G

bomberesque

The first scratch on a beautifully expensive bike; it's generically known as the cherry scratch and every bike gets one.

In fact, most bikes lose the paint at the drop-out as the axle and QR grind it off through use, could this be it? Benj is right to ask fo a photo, can't really tell without. Probably no big, honest. If the chain has gone off the smallest ring, then you do need to get the limit screws adjusted on the rear deurailleur, but although the shop will certainly do the adjustment for you I wouldn't expect anything further from them unless real damage has occurred and is clearly due to their bad set-up

bikes get scratched, even *very* expensive ones (just got the cherry scratch on my Ibis Tranny so I know how you feel)

type_grim

Bomberesque - thanks for your comment.

I think you are right in what you are saying. It's just so frustrating that you spend that kind of money, for something like this to happen.

I have attached a few pics; you will have to excuse the quality, they were taken in the garage tonight!

I will try get some proper ones up with the wheel out, in daylight!









G

The Northern Monkey

That looks a bit odd..

Would the chain actually fit between the chainstay and small sprocket?

kinda looks as though the chain would have been rubbing against the chainstay constantly while its rotating as thought the frame is too close to the cassette..

Do you have a pic looking vertically down on the cassette/chainstay?


Btw... that looks a lot worse than what I was expecting! I can't say i've seen something as bad as that just from the chain slipping off!

nicklouse

damage like that can happen on descents. bumps and a slack chain.

The Northern Monkey

nicklouse wrote:

damage like that can happen on descents. bumps and a slack chain.

Yea was going to say a slack chain... one too many links maybe?

nicklouse

bigbenj_08 wrote:

nicklouse wrote:

damage like that can happen on descents. bumps and a slack chain.

Yea was going to say a slack chain... one too many links maybe?

nope nothing to do with chain length.

usage.

type_grim

I haven't got a shot from above, no. I will take one tomorrow.

I don't think the chain could fit between the smallest rear sprocket and the frame.

I have mainly cycled into work, with two off road rides every other week. I haven't bought the bike to use for DH, i take it gently on descents!

I reckon i have done 250 miles at most on it, all of which has been taken easily.

I am a lot more cautious when riding with the bike, being Carbon.

On my old Rockhopper, i'd thrash it everywhere; this one gets a lot more respect.

It just seems odd that i haven't done that many miles, and i have a wear mark like that.

paul.skibum

As Nick says its usage .

The problem is running the chain on the smallest cog on rough ground - need to be more selective on your gears - big up front and something in the middle of the cassette will tighten the chain up to stop it slapping but middle front and smallest rear its going to jump and skip and smash into the frame.

Dont blame the LBS blame the rider! Sorry chum.