Carbon fiber thoughts

wrote in message
oups.com...

I've never used a 12 tooth cog, and the 13 very
rarely, so I blame the frame builder, Marinoni.

Yeah, you college professor types are all weak kneed and thin. What was it
Shakespeare wrote about Brutus?

"Tom Kunich" cyclintom@yahoo. com wrote in message
ink.net...
wrote in message
oups.com...

I've never used a 12 tooth cog, and the 13 very
rarely, so I blame the frame builder, Marinoni.

Yeah, you college professor types are all weak kneed and thin. What was it
Shakespeare wrote about Brutus?

My mistake - Cassius: "Yond Cassius has a lean and hungry look; He thinks
too much: such men are dangerous."

in message . net, Tom
Kunich ('cyclintom@yahoo. com') wrote:

wrote in message
oups.com...

I've never used a 12 tooth cog, and the 13 very
rarely, so I blame the frame builder, Marinoni.

Yeah, you college professor types are all weak kneed and thin. What was
it Shakespeare wrote about Brutus?

"Brutus is an honourable man."

Nah, doesn't describe anyone 'round here.

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/

I'm fed up with Life 1.0. I never liked it much and now it's getting
me down. I think I'll upgrade to MSLife 97 -- you know, the one that
comes in a flash new box and within weeks you're crawling with bugs.

"Simon Brooke" wrote in message
...
in message . com,
') wrote:

(http://www.velonews.com/tour2007/tec...s/12564.0.html )

"The spares get washed and tuned every other day and God forbid if
someone crashes, no matter how minor, mechanics change out the
handlebar, stem and fork - at the very least. If the frame is so much
as suspected to be damaged it's changed out as well. Imagine if two or
three guys crash in one day, whew"

This is one reason why I am very reluctant to spend huge sums of money
on a composite frame that could be history after a single crash. For
all the advances in composites de-lamination and stress points are
still a unresolved issue. Now 3d weaved composites my resolve the de-
lamination issue (http://www.netcomposites.com/news.asp?3874 ).

I think this one is overblown. Yes, carbon fibre can be damaged in a
crash,
in ways which are not visible without a stress jig. But I crashed a carbon
fibre bike at 46mph into solid granite two years ago. We swapped out the
forks and handlebars on the precautionary principle, and sent the frame
back to the makers to be checked on their stress jig. It was fine, and I'm
still riding it.

http://www.jasmine.org.uk/dogfood/story/article_41.html

Carbon is /incredibly/ strong and resilient.

Yes, but there is no relationship between observable damage leading to
either (1) no problems or (2) failure. So, every time there *might* be a
problem (after a crash, or a fall, or a tipover while waiting for your
latte) you either (1) replace the frame or (2) worry.

How do you think the Boeing folks are addressing this? Their new
'dreamliner' is CF!


--
(Simon Brooke) http://www.jasmine.org.uk/~simon/

[ This .sig subject to change without notice ]

giorgitd wrote:

Yes, but there is no relationship between observable damage leading to
either (1) no problems or (2) failure. So, every time there *might* be a
problem (after a crash, or a fall, or a tipover while waiting for your
latte) you either (1) replace the frame or (2) worry.



Apparently, Lotto and Milram take option (b)

http://www.velonews.com/tour2007/new...s/12634.0.html

(Lotto mechanic "We had a good look over Robbie McEwen's bike after his crash yesterday (Sunday), but all we had to do was change his handlebar tape."
....
On very rare occasions, they have to change a bike too.

"It's not often we change bikes because the frame is broken," added Rombauts, who tends to the bike of top German sprinter Erik Zabel.

Dan

On Jul 7, 6:22 am, "Tom Kunich" cyclintom@yahoo. com wrote:
"Tom Kunich" cyclintom@yahoo. com wrote in .earthlink.net...

wrote in message
roups.com...

I've never used a 12 tooth cog, and the 13 very
rarely, so I blame the frame builder, Marinoni.

Yeah, you college professor types are all weak kneed and thin. What was it
Shakespeare wrote about Brutus?

My mistake - Cassius: "Yond Cassius has a lean and hungry look; He thinks
too much: such men are dangerous."

I thought Cassius had feet of Clay.

-ilan

wrote:

I thought Cassius had feet of Clay.


Wasn't he involved in the Boxer Rebellion?

in message , giorgitd
') wrote:


"Simon Brooke" wrote in message
...
in message . com,
') wrote:

(http://www.velonews.com/tour2007/tec...s/12564.0.html )

"The spares get washed and tuned every other day and God forbid if
someone crashes, no matter how minor, mechanics change out the
handlebar, stem and fork - at the very least. If the frame is so much
as suspected to be damaged it's changed out as well. Imagine if two or
three guys crash in one day, whew"

This is one reason why I am very reluctant to spend huge sums of money
on a composite frame that could be history after a single crash. For
all the advances in composites de-lamination and stress points are
still a unresolved issue. Now 3d weaved composites my resolve the de-
lamination issue (http://www.netcomposites.com/news.asp?3874 ).

I think this one is overblown. Yes, carbon fibre can be damaged in a
crash,
in ways which are not visible without a stress jig. But I crashed a
carbon fibre bike at 46mph into solid granite two years ago. We swapped
out the forks and handlebars on the precautionary principle, and sent
the frame back to the makers to be checked on their stress jig. It was
fine, and I'm still riding it.

http://www.jasmine.org.uk/dogfood/story/article_41.html

Carbon is /incredibly/ strong and resilient.

Yes, but there is no relationship between observable damage leading to
either (1) no problems or (2) failure. So, every time there *might* be a
problem (after a crash, or a fall, or a tipover while waiting for your
latte) you either (1) replace the frame or (2) worry.

How do you think the Boeing folks are addressing this? Their new
'dreamliner' is CF!

If you buy a new Look frame, it comes with a certificate of it's individual
readings on the stress test rig. If you crash it, send it back to Look,
they put it back on the rig, check the readings, if within a specified
margin of the original it's good, otherwise you scrap it. Other
manufacturers don't give you individual readouts for each frame, but will
still have type parameters for each model, and again if on test the frame
is within parameters it's OK, if not, scrap it.

Personally I love carbon fibre frames. They perform much better and are at
the same time more comfortable than any other frame material.

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/

;; IE 3 is dead, but Netscape 4 still shambles about the earth,
;; wreaking a horrific vengeance upon the living
;; anonymous

On Jul 9, 10:19 am, "giorgitd"
wrote:
"Simon Brooke" wrote in message

I think this one is overblown. Yes, carbon fibre can be damaged in a
crash,
in ways which are not visible without a stress jig. But I crashed a carbon
fibre bike at 46mph into solid granite two years ago. We swapped out the
forks and handlebars on the precautionary principle, and sent the frame
back to the makers to be checked on their stress jig. It was fine, and I'm
still riding it.

http://www.jasmine.org.uk/dogfood/story/article_41.html

Carbon is /incredibly/ strong and resilient.

Yes, but there is no relationship between observable damage leading to
either (1) no problems or (2) failure. So, every time there *might* be a
problem (after a crash, or a fall, or a tipover while waiting for your
latte) you either (1) replace the frame or (2) worry.

How do you think the Boeing folks are addressing this? Their new
'dreamliner' is CF!

I bet that CF damage isn't actually unobservable. People
make it sound invisible like the Fantastic Four chick, but
it's more likely that damaged CF that mysteriously breaks
later while "JRA" was cracked and/or delaminated all along,
it's just not cracking that the average bikie can spot
with the naked eye under cursory inspection.

Most frame failures aren't catastrophic, while most fork
failures are. So why do people put CF forks on non-CF
frames rather than the other way around? Either the
forks are overbuilt, people have no conception of risk
analysis, or some combination thereof.

Airliners, unlike most bicycles, come with thorough
periodic inspection protocols. That's not a guarantee,
but they aren't directly comparable.

Ben

wrote in message
ups.com...
On Jul 7, 6:22 am, "Tom Kunich" cyclintom@yahoo. com wrote:
"Tom Kunich" cyclintom@yahoo. com wrote in
.earthlink.net...

wrote in message
roups.com...

I've never used a 12 tooth cog, and the 13 very
rarely, so I blame the frame builder, Marinoni.

Yeah, you college professor types are all weak kneed and thin. What was
it
Shakespeare wrote about Brutus?

My mistake - Cassius: "Yond Cassius has a lean and hungry look; He thinks
too much: such men are dangerous."

I thought Cassius had feet of Clay.

Is that why the Bear went down? Or was it the Flashing Fists of Fury?