H+Son rim failure, Mr. Brandt, your thoughts?

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?

- chris

Chris Allick wrote:

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?

It's not right but the story may be correct. From the pictures it
seems the rim split down the center of its bed between sidewalls, but
I can't be sure because the lighting is poor and the rim black.

That's another point. I haven't seen such a split since black hard
anodized rims first appeared on the market in the 1970's. What brand
rim is it and is there a better picture of the wheel with no tire
remains obscuring the rim? I can see that it must have been loud
because the split in the inner tube is the reult of an instant
"air-out" like ones that I have heard.

So when was this wheel bought (built) and how about a closeup of the
fractured surface.

Jobst Brandt

On Sun, 7 Dec 2008 16:38:21 -0800 (PST), Chocobot
wrote:

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?

- chris

Dear Chris,

What was the tire width and inflation?

Cheers,

Carl Fogel

On Dec 7, 4:38 pm, Chocobot wrote:
http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?


Totally WAG: Fixed gear? Doing a skid? Forces of braking from hub
added spoke tension and longitudinal force at rim? Possibly existing
crack at spoke nipple bed split open. Then inner tube blew up forcing
crack further apart?

wrote:
Chris Allick wrote:

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?

It's not right but the story may be correct. From the pictures it
seems the rim split down the center of its bed between sidewalls, but
I can't be sure because the lighting is poor and the rim black.

That's another point. I haven't seen such a split since black hard
anodized rims first appeared on the market in the 1970's. What brand
rim is it and is there a better picture of the wheel with no tire
remains obscuring the rim? I can see that it must have been loud
because the split in the inner tube is the reult of an instant
"air-out" like ones that I have heard.

So when was this wheel bought (built) and how about a closeup of the
fractured surface.

Jobst Brandt

New product; H+Son just started shipping these new rims
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

Dan O wrote:
On Dec 7, 4:38 pm, Chocobot wrote:
http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?


Totally WAG: Fixed gear? Doing a skid? Forces of braking from hub
added spoke tension and longitudinal force at rim? Possibly existing
crack at spoke nipple bed split open. Then inner tube blew up forcing
crack further apart?

Not quite. The tube burst because the rim failed.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

wrote in message
...
On Sun, 7 Dec 2008 16:38:21 -0800 (PST), Chocobot
wrote:

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?

- chris

Dear Chris,

What was the tire width and inflation?

Cheers,

Carl Fogel

You're on the right path, but it probably still needed a bit of help to
split like that, probably caused by an issue with the die such that the
rim was scored (a groove cut into it lengthwise) as it was extruded.
I've see it before.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com

On Dec 7, 10:26*pm, "Mike Jacoubowsky" wrote:
wrote in message

...



On Sun, 7 Dec 2008 16:38:21 -0800 (PST), Chocobot
wrote:

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. *Does this seem right?

- chris

Dear Chris,

What was the tire width and inflation?

Cheers,

Carl Fogel

You're on the right path, but it probably still needed a bit of help to
split like that, probably caused by an issue with the die such that the
rim was scored (a groove cut into it lengthwise) as it was extruded.
I've see it before.

When I was in the mechanic business, there was a run of hard anodized
26" Ritchey Vantage Comps that had just such a problem-- a groove
running down the inside rim wall, so distinct and centered that it
looked intentional. I saw a couple of those things crack and split
along the groove, though nothing that spread wide open like the H+Son
rim.

Chalo

On Sun, 7 Dec 2008 20:26:36 -0800, "Mike Jacoubowsky"
wrote:

wrote in message
.. .
On Sun, 7 Dec 2008 16:38:21 -0800 (PST), Chocobot
wrote:

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?

- chris

Dear Chris,

What was the tire width and inflation?

Cheers,

Carl Fogel

You're on the right path, but it probably still needed a bit of help to
split like that, probably caused by an issue with the die such that the
rim was scored (a groove cut into it lengthwise) as it was extruded.
I've see it before.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com

Dear Mike,

If it turns out to be just an ordinary narrow tire and ordinary
pressure, then a bad rim is the most likely explanation.

But running an over-width tire at excessive pressure is likely to
split a good rim the same way:
http://groups.google.com/group/rec.b...ce37398fc401ff

The rider doesn't look like the 265-lb Clydesdale in that old thread,
but skidding sideways might make up for the lighter weight.

If it turns out to be a 38 mm tire at 80 psi, ouch!

Cheers,

Carl Fogel

Chocobot wrote:

http://ganrin.blogspot.com/2008/11/i...-mine-but.html

That is the story. Does this seem right?


I clicked on the second photo and found a link to a larger size:

http://www.flickr.com/photos/ganring...14948/sizes/l/

The inner rim wall is very thin looking. Just eyeball estimating, it looks less than 1/2 or even 1/3 mm to me.