metal matrix long-term failure rate - Specialized, Duralcan

I had one for a number of years and thousands of training
and racing miles. It held up fine. It is now someone elses
and I still see it at the races. The same can be said for a
friend of mines.

"Chad" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I recall that metal matrix frames of the kind that
Duralcan manufactured and Specialized called M2, M2X, etc.
were the subject of some controversy in the 90s.

See tinyurl.com2tuuuOpen ↗ for instance

Their stiffness and low elongation factor was sometimes
linked to unfortunate failure modes and rates.

I am very curious, especially after coming upon a
beautiful '98 M2 Allez Pro frame for sale, whether the
jury is in on this material. Am I correct that bicycles
are no longer made using metal matrices?

Is this material as safe as, say, pure 6061 or 7005, or is
it been demonstrated to be a disaster waiting to happen?

thanks,

Chad

Chad AT alumni DOT unh DOT edu

The only Specialized bikes that I KNOW had a problem with
breaking were the M4 models. They liked to crack at the
chainstay.

I've owned an M2 Road Pro, an M4, and now an E5 S-Works. I
had the M2 for about 5 years without a problem, the M4 for
2-3 without a problem, and now the E5 for about a year.

I had friends go thru a few M4s, but I must've gotten a
good one...

HTH,

M

"Chad" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I recall that metal matrix frames of the kind that
Duralcan manufactured and Specialized called M2, M2X, etc.
were the subject of some controversy in the 90s.

See tinyurl.com2tuuuOpen ↗ for instance

Their stiffness and low elongation factor was sometimes
linked to unfortunate failure modes and rates.

I am very curious, especially after coming upon a
beautiful '98 M2 Allez Pro frame for sale, whether the
jury is in on this material. Am I correct that bicycles
are no longer made using metal matrices?

Is this material as safe as, say, pure 6061 or 7005, or is
it been demonstrated to be a disaster waiting to happen?

Duralcan made the alloy. Anodizing, Inc. drew the tubes and
made the frames here in Portland. The first frames were the
M2 Stumpjumpers had some failures of dubious cause which
resulted in the addition of gussets. There was no change in
material. The problem with metal matrix is drawing the tubes
while maintaining a good distribution of the ceramic
particles. It took Anodizing a while to get it right, but it
got it right before the bikes went into production. The
straight gauge frames, like the M2 road bike, turned out to
be pretty tough. I think they fell out of popularity (and
out of production) due to weight and the demand for thin,
highly shaped tubes. Butting was difficult with MM, and
making frames in the U.S. was not cheap. -- Jay Beattie.

It makes more sense to me to make complicated welded
structures like the frame out of easy to work with materials
and save the difficult to work with materials for non welded
simple parts like the chainrings and handle bars and maybe
the stem and seatpost.

I'm especially impressed that Jay Beattie weighed in, one of
the original participants in the threads from the 90s. Long-
term R.B.T !

My intuition is that Al is stiff enough already without
adding oxide particles.

I think I may be picking up the M2 road frame, we'll see how
it behaves. Perhaps I'll report later.

Thanks to all responders.

Chad

chad AT alumni DOT unh DOT edu