Mavic X138 rim crack

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mercalia
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Location: london South

Mavic X138 rim crack

Postby mercalia » 20 Sep 2014, 6:01pm

I have been using for the last few months the original rear wheel that my Dawes 1-Down came with a Mavic X138 ( must be 10+ years old but on original rim and probably done no more than 3000 miles max) & noticed the other day a crack around one of the spoke eyelets. Only one, the rest of the wheel fine. I dont know what that spoke was doing as the wheel is still true. Any opinions whether the wheel is still safe to use?

mavic x138 rim - Copy.JPG
crack at spoke Mavic X138 rim click to enlarge

alicat
Posts: 112
Joined: 6 Feb 2012, 6:20pm

Re: Mavic X138 rim crack

Postby alicat » 20 Sep 2014, 8:34pm

No - there is another crack on the sidewall.

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Mavic X138 rim crack

Postby Brucey » 20 Sep 2014, 9:23pm

at present the rim isn't about to snap in half like a carrot and nor is the tyre about to blow off or anything. So arguably the wheel is no more dangerous than if you had (say) broken a spoke.

But.... where there is one rim crack there are invariably others, sooner or later... so I'd suggest that the wheel is living on borrowed time.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

tim-b
Posts: 1010
Joined: 10 Oct 2009, 8:20am

Re: Mavic X138 rim crack

Postby tim-b » 21 Sep 2014, 7:53am

Hi

IMHO, recycle bin it

If the rim breaks...
What will happen if it snags your brake unexpectedly and damages your frame?
Or spears the back of your leg?
Or just leaves you stranded?

Regards
tim-b
~~~~¯\(ツ)/¯~~~~

User avatar
squeaker
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Joined: 12 Jan 2007, 11:43pm
Location: Sussex

Re: Mavic X138 rim crack

Postby squeaker » 21 Sep 2014, 8:18am

Recycle bin ASAP, IMHO.
"42"

alicat
Posts: 112
Joined: 6 Feb 2012, 6:20pm

Re: Mavic X138 rim crack

Postby alicat » 21 Sep 2014, 9:38am

Brucey

I respect your technical expertise so this is a genuine question. I can see three cracks, one on each of the sides next to the spoke hole and a further large crack on the sidewall.

Are you really saying the rim is merely 'on borrowed time'? I personally wouldn't take the bike out until the rim is replaced. Am I being a wuss?

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Mavic X138 rim crack

Postby Brucey » 21 Sep 2014, 10:24am

this rim is (IIRC) a double-walled rim with a single eyelet. I wouldn't choose to ride on a rim in that state but I have seen plenty of people who have (unwittingly) ridden on rims that are far worse than that. Such damage is only noticed by many riders once it puts the wheel out of true. I'd certainly ride home on that rim, but I might lash the spoke so that it couldn't move.

The main forces in the rim put the rim into compression lengthwise (circumferentially) and in addition the tyre is trying to open the rim well outwards. In effect here, there is a big hole in the rim inner wall which doesn't affect the latter greatly and will only greatly affect the former if it is repeated at several locations. In the region of the damage, you could argue that the rim is effectively a single walled rim with a missing spoke in this locality. If the rim's stiffness was greatly compromised, it is likely that the wheel would already have run out of true.

I compared with a broken spoke for a reason; IMHO a significant hazard is what might happen if the end of the spoke comes free. I have seen loose spokes get snarled in the transmission, or even poke their way through a tyre sidewall.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

mercalia
Posts: 11102
Joined: 22 Sep 2013, 10:03pm
Location: london South

Re: Mavic X138 rim crack

Postby mercalia » 21 Sep 2014, 10:32am

I have ordered a new wheel but I only found the cracks when I was out on a day trip having done about 20 miles. I went home and the cracks hadnt got any larger. So I was wondering if it was stable - unlike many other pictures of cracked rims just the one & the wheel still true. I only noticed it as I was sat down for a munch on a grass bank and that part of the wheel caught my eye in the sun, pure luck. never had a cracked rim before - spokes yes- so wasnt looking for it or exepcting it

alicat
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Joined: 6 Feb 2012, 6:20pm

Re: Mavic X138 rim crack

Postby alicat » 21 Sep 2014, 12:11pm

Thanks, Brucey. I always learn from your posts.

mercalia
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Joined: 22 Sep 2013, 10:03pm
Location: london South

Re: Mavic X138 rim crack

Postby mercalia » 24 Sep 2014, 8:45pm

well I had a look today closer ar rim and other less obvious cracks appearing around spoke eyelets. I'll be glad when the new wheel arrives. I wonder is this way that all old rims go in the end as the alloy gets old? Never had this happen to me before. A result of single spoke eyelet in rim?

JohnW
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Joined: 6 Jan 2007, 9:12pm
Location: Yorkshire

Re: Mavic X138 rim crack

Postby JohnW » 25 Sep 2014, 1:29am

squeaker wrote:Recycle bin ASAP, IMHO.


+1

mercalia
Posts: 11102
Joined: 22 Sep 2013, 10:03pm
Location: london South

Re: Mavic X138 rim crack

Postby mercalia » 25 Sep 2014, 11:09am

well I'll recycle the rim. get a new one to practice wheel building as the hubs and spokes are still ok

JohnW
Posts: 6201
Joined: 6 Jan 2007, 9:12pm
Location: Yorkshire

Re: Mavic X138 rim crack

Postby JohnW » 25 Sep 2014, 11:24am

mercalia wrote:well I had a look today closer ar rim and other less obvious cracks appearing around spoke eyelets. I'll be glad when the new wheel arrives. I wonder is this way that all old rims go in the end as the alloy gets old? Never had this happen to me before. A result of single spoke eyelet in rim?


The way my rims become life expired is that the braking surface of the rim simply wears away - the face of the rim becomes concave as it losses strength and the face becomes concave. If the rim is going to fail, it usually fails at the joint. Eventually, if not replaced in time, the rim collapses spectacularly with sound effects that would surprise you. It's happened to me just once - thankfully on the back wheel. It was not a Mavic rim.

We're in a hilly area, and that affects the mileage we get from a rim, but whereas 20+ years ago I was getting 15,000 - 17,000 miles from a Mavic rim, I get barely 10,000 miles from a Mavic now, and I am changing my choice.

The defect related by the OP has caused me to very closely inspect the remaining Mavics on my bikes..........personally, I haven't experienced a similar issue myself - not yet, anyway - but even so it confirms my decision to choose a different rim manufacturer. Don't however, underestimate the wheelbuilder's part in it all.

JohnW
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Joined: 6 Jan 2007, 9:12pm
Location: Yorkshire

Re: Mavic X138 rim crack

Postby JohnW » 25 Sep 2014, 11:31am

Brucey wrote:at present the rim isn't about to snap in half like a carrot and nor is the tyre about to blow off or anything. So arguably the wheel is no more dangerous than if you had (say) broken a spoke...........


It's a brave man who puts that in writing, Brucey.

Brucey
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Re: Mavic X138 rim crack

Postby Brucey » 25 Sep 2014, 11:46am

you can say the same thing about many remarks that are taken out of context....

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~