Boxerworks.com

Engineers will prescribe a wheel to be built within certain performance / design characteristics,
and reality may indeed push our adventures past the limits of that performance envelope.
The singular circumstance of hitting one thing with a force sufficient
to cause a catastrophic failure of a structurally sound wheel is certainly possible.
But a significantly greater possibility if that wheel is not structurally sound.
The same will be true if those wheels are subjected to repetitive stress ...
Failure of metals is more frequently the result of fatigue - a function of accumulated repetitive stress.

NO wheel is able to differentiate between cobblestones, pot-holes, or other road anomalies –
Forces applied and the response of a given design to those forces will be just the same.

I've not much experience with cobblestones – but plenty with "cobbled" roads,
and I'd hate to think that there will be anyone out there on pre-recall flakes thinking:
"Not to worry, ain't no cobblestones in my neighborhood"

Kurt in S.A.[/quote]

Victoria Canada
Vancouver Canada
Edinburgh Scotland
Sacramento California

Cleveland Ohio has one short street of cobblewood. Yes, cut pieces of wood with the end grain up. Really fun in the rain on a bike.

ME 109 wrote: I would think that all these recall snowflakes would show signs of cracking long before a major problem presented itself.

YOU TALKIN' TO ME?!!!!!

Major Softie wrote:

ME 109 wrote: I would think that all these recall snowflakes would show signs of cracking long before a major problem presented itself.

YOU TALKIN' TO ME?!!!!!

I quite clearly wrote 'itself'
Not 'himself'

Just to clarify, the original recall was only for the front wheel and not the rear. Or at least this was as far as I understood. I traded a set of wheels probably 10 years ago and got a recall front. My local dealer (since retired) swapped it out for a new wheel.

ME 109 wrote:

Major Softie wrote:

ME 109 wrote: I would think that all these recall snowflakes would show signs of cracking long before a major problem presented itself.

YOU TALKIN' TO ME?!!!!!

I quite clearly wrote 'itself'
Not 'himself'

I figured that was just a dehumanizing extension of the insult.

Flatwins wrote:Just to clarify, the original recall was only for the front wheel and not the rear. Or at least this was as far as I understood. I traded a set of wheels probably 10 years ago and got a recall front. My local dealer (since retired) swapped it out for a new wheel.

And I thought you had to bring the wheel in on the bike so they could check the frames serial number?

The serial numbers are on the wheels themselves. What I was told, the dealer then charges off BMW for the wheel and service. No need to bring the bike. We'll see and report.

Original reason for the failures and FREE change-out was when the casting cooled, the thick hub and the thinner spoke with NO reinforcements, cooled at too much a different rate, setting up stresses that made cracking/breaking off VERY likely...and they did.
Aluminum is more succeptable to this than Iron, but any casting not designed adequately will behave this way.

So it may be fair to say that a new, unused , and unreinforced snowflake could have been heat treated (normalised) to relieve the inherent stresses and become fault free?

....I wonder if the re-enforcing web was designed to help resist the shrinkage during the wheel cooling process, or to brace the potentially 'stressed after cooled' spokes under normal riding conditions?

I wonder if I should stop wondering about things too much?