HOT: Active* forum members generally gain 5% discount at starbike.com store!
Weight Weenies
* FAQ    * Search    * Trending Topics
* Login   * Register
HOME Listings Articles FAQ Contact About




Post new topic Reply to topic  [ 18 posts ] 
Go to page Previous  1, 2
Author Message
 Post subject:
PostPosted: Wed Nov 10, 2004 6:28 pm 
Offline

Joined: Thu Oct 07, 2004 7:33 pm
Posts: 243
Location: Barcelona/Torino
Itm millenium is also seen in the pro's pelloton; but I have heard that are a bit flexy (alu stem and bar), or a bit more flexy than Newton Family; but they are also cheaper. Has anyone tried Selcof carbon stems? are they reliable? And the Fsa's one? what about? they aren't the lighest out there but aren't also so expensive.

_________________
flat transitioner shimanoist


Top
 Profile  
 
 Post subject:
PostPosted: Wed Nov 10, 2004 6:48 pm 
Offline
User avatar

Joined: Wed Nov 10, 2004 4:39 pm
Posts: 1008
Location: Des Moines, IA
drjones96 wrote:
Aluminum (metals) - Take a paperclip and bend it back and forth over and over. Eventually it will snap. You are plasticly deforming the paperclip until ultimatly it reaches the end of it's fatigue life.

Now think about a similar peice of carbon/epoxy composite. Bend it once and it's pretty much done for.


Ok take a piece of carbon/epoxy, try to bend it. Take it to a kitchen and hit it with a rolling pin, take it to the shop use to sets of plier and try to bend it, ok put it in a vise and smack it with a hammer. Get my point?

Also, AL doen't act like your steel paper clip. AL will snap just as quickly.

Read some articales about the EFB tests and look at what they have come up with about the stiffness of frames and a AL frame getting "Soft". It is in your head, frames don't get soft. Al failes like carbon does in one big explosion that you don't see coming. Have you seen someone brake a AL handle bar? It is quick and dramatic...it snaps/doesn't bend.


Top
 Profile  
 
 Post subject:
Posted: Wed Nov 10, 2004 6:48 pm 


Top
  
 
 Post subject:
PostPosted: Wed Nov 10, 2004 7:28 pm 
Offline
User avatar

Joined: Thu Nov 04, 2004 10:56 pm
Posts: 3722
Location: Wichita, KS
After 4 years of engineering school I've seen my share structural testing.
I know what you're talking about though....if it has failed, it has failed...what more do you need to talk about. There are a variety of alloys though...some soft and some hard.

The harder alloys will fail similar to carbon. 6061 will bend where a harder alloy like 7075 (my wife's bars are made of 7075) will snap.

If you're interested take a look at a Stress vs Strain curve comparison for Aluminum (take your pick of the most widely used alloys in cycling) and Carbon/Epoxy composite. What you should see is the difference in the modulus of elasticity between the two (carbon should be higher) and at the top of the curve Aluminum will reach a point of ultimate strengh a while before failure. Carbon will not reach such a point before failure. That, I believe, is the diffence in the material......yeah yeah yeah....blah blah blah....engineering garbage that doesn't always apply in real world conditions.....

I'm not going to split hairs here....I think most carbon cycling components are built well enough to do the job under normal conditions. (That should include heavier riders)


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 18 posts ] 
Go to page Previous  1, 2


Who is online

Users browsing this forum: Bing [Bot], Google [Bot], shoemakerpom2010, wheelsONfire and 41 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  

   Similar Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. Light Road Hubs

[ Go to page: 1, 2 ]

in Road

reeper250

15

1368

Tue Apr 22, 2014 10:48 pm

Slagter View the latest post

There are no new unread posts for this topic. Light bike or stiff bike?

[ Go to page: 1, 2, 3 ]

in Road

Kermithimself

30

2106

Sat Sep 20, 2014 8:03 am

pagey View the latest post

There are no new unread posts for this topic. Light weight helmet

[ Go to page: 1, 2 ]

in Road

MNX1024

21

1550

Thu Sep 04, 2014 4:56 am

Johnny Rad View the latest post

There are no new unread posts for this topic. Light weight carbon handlebars

[ Go to page: 1, 2, 3 ]

in Road

addictR1

32

4467

Sat Jul 26, 2014 10:09 pm

PuroScattista View the latest post

There are no new unread posts for this topic. AEST light weight crankset

in Road

yumseyo

7

1736

Fri Feb 14, 2014 9:13 pm

yumseyo View the latest post


It is currently Sat Sep 20, 2014 5:57 pm

All times are UTC + 1 hour




Advertising   –  FAQ   –  Contact   –  Convert   –  About

© Weight Weenies 2000-2013
hosted by starbike.com


How to get rid of these ads? Just register!


Powered by phpBB