Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Frame Questions

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Frame Questions

Old 09-04-07 | 01:51 PM
  #1  
Thread Starter
Junior Member
 
Joined: Sep 2007
Posts: 14
Likes: 0
From: Kentucky

Bikes: Giant Sedona (unknown year)

Frame Questions

So I have a Giant Sedona, it's from the early 90's but Im not entirely sure, it was my dads bike and I fixed it up.
its seems to be study, but I had a question. is there any way to tell about the frame material?

it says Quad Butted Cro-moly.....i dunno what that means. I mean it's decently light but it's not (not heavy) either. (if I could find the date on my bike it'd be easier, any ideas?)

I had heard alot about aluminum frame's. now here's my worry. I dont want the frame to fatigue over time or break or w/e cause I know there much weaker than steel/titanium etc.

but then again i only ride around the city, and "occasionally" take it a little off the beaten path (dirt/grassy road etc....hey it's kentucky lol)

IF my frame was aluminum, would that cause any harm to it over time, or when they mean "frame" bending do they mean like if ur jumping off rocks and hardcore mountain biking with it?

Thanks!

OH BTW does anyone know if the giants in particular the giant sedona's are a good brand/type or bike?

thx
MercenaryFH is offline  
Reply
Old 09-04-07 | 01:54 PM
  #2  
Your mom
15 Anniversary
 
Joined: Aug 2006
Posts: 2,545
Likes: 2
Cro-Moly is steel (I think chromium/molybdenum, the metals they mix in with the iron). It's standard stuff. Quad butted is nice-ish. Don't worry about it at all; get out and ride!
tellyho is offline  
Reply
Old 09-04-07 | 03:35 PM
  #3  
Sheldon Brown's Avatar
Gone, but not forgotten
Sheldon Brown Memorial - Titanium
20 Anniversary
 
Joined: Jul 2002
Posts: 2,301
Likes: 12
From: Newtonville, Massachusetts

Bikes: See: https://sheldonbrown.org/bicycles

Originally Posted by MercenaryFH
So I have a Giant Sedona, it's from the early 90's but Im not entirely sure, it was my dads bike and I fixed it up.
its seems to be study, but I had a question. is there any way to tell about the frame material?

it says Quad Butted Cro-moly.....i dunno what that means. I mean it's decently light but it's not (not heavy) either. (if I could find the date on my bike it'd be easier, any ideas?)

I had heard alot about aluminum frame's. now here's my worry. I dont want the frame to fatigue over time or break or w/e cause I know there much weaker than steel/titanium etc.

but then again i only ride around the city, and "occasionally" take it a little off the beaten path (dirt/grassy road etc....hey it's kentucky lol)

OH BTW does anyone know if the giants in particular the giant sedona's are a good brand/type or bike?
These were very nice bikes, definitely a keeper. Your dad has good taste.

Originally Posted by tellyho
Cro-Moly is steel (I think chromium/molybdenum, the metals they mix in with the iron). It's standard stuff. Quad butted is nice-ish. Don't worry about it at all; get out and ride!
Good for you, you are one of the rare few who can spell molybdenum! (I'm sure that's the main reason for abbreviating it to "moly" ;-)

Quad butted is more than "nice-ish", it's as good as it gets.

Sheldon "Giants Are Good" Brown
Sheldon Brown is offline  
Reply
Old 09-04-07 | 03:36 PM
  #4  
waterrockets's Avatar
Making a kilometer blurry
 
Joined: May 2006
Posts: 26,170
Likes: 93
From: Austin (near TX)

Bikes: rkwaki's porn collection

Yep, it's steel. I commute, MTB, train, tandem, and race on steel bikes. You're good to go -- go work on the motor!

Giants are a popular brand with some ProTour sponsorship (Giant bikes race in the Tour De France). I have several friends racing on them.

FWIW, Aluminum is in no more danger of failure than any other frame material. All good bikes are built to withstand the expected loads and still be as light as possible, given the budget. Riding off-road on light bumps won't challenge the frame much, but be careful with the wheels -- they're much more susceptible to rough road problems.
waterrockets is offline  
Reply
Old 09-04-07 | 08:38 PM
  #5  
Thread Starter
Junior Member
 
Joined: Sep 2007
Posts: 14
Likes: 0
From: Kentucky

Bikes: Giant Sedona (unknown year)

Oh. so theirs no such thing as cro-moly quad butted aluminum eh(do most steel bikes use that?), im kinda glad it's steel. I mean i dont hardcore offroad but hell I like to take my bike on the dusty trail. i just heard that aluminum it will like bend and break over time?
but giants good quality im assuming :-D

thanks so much guys
MercenaryFH is offline  
Reply
Old 09-04-07 | 08:50 PM
  #6  
Sheldon Brown's Avatar
Gone, but not forgotten
Sheldon Brown Memorial - Titanium
20 Anniversary
 
Joined: Jul 2002
Posts: 2,301
Likes: 12
From: Newtonville, Massachusetts

Bikes: See: https://sheldonbrown.org/bicycles

Originally Posted by MercenaryFH
Oh. so theirs no such thing as cro-moly quad butted aluminum eh
Nope, no more than wood steel. Totally different materials.

Originally Posted by MercenaryFH
i just heard that aluminum it will like bend and break over time?
Sounds like you have been listening to unscrupulous or ignorant salesmen! See: https://sheldonbrown.com/frame-materials

Sheldon "Metal Is Good" Brown
Sheldon Brown is offline  
Reply
Old 09-04-07 | 08:54 PM
  #7  
lebowitz's Avatar
Craig A. Lebowitz
 
Joined: Oct 2004
Posts: 372
Likes: 0
From: Washington, DC

Bikes: 1984 Trek 520 | 2002 Specialized Hardrock

the problem with aluminum is that is actually can not bend much over time without failing. It can bend very little before deforming permanently (like an aluminum can) and never returning to the original shape. So the failure case is usually one traumatic incident that wrecks it structually.

Steel can bend and be bent back and that is essentially what makes it resilient and desirable as a frame material (along with its vibration absorption property)

Originally Posted by MercenaryFH
i just heard that aluminum it will like bend and break over time?
lebowitz is offline  
Reply
Old 09-04-07 | 09:42 PM
  #8  
Thread Starter
Junior Member
 
Joined: Sep 2007
Posts: 14
Likes: 0
From: Kentucky

Bikes: Giant Sedona (unknown year)

oh I see. So....for like "riding" purposes like Im going to be doing, I mean even tho my bike is steel im just curious, but for slight offroad but mostly city riding (assuming u dont get hit by a car/in an accident with your bike) would aluminum hold up over a long time? or eventually fatigue by being just ridden on in the city and kinda break that way?
MercenaryFH is offline  
Reply
Old 09-04-07 | 09:54 PM
  #9  
well biked's Avatar
Senior Member
Titanium Club Membership
20 Anniversary
 
Joined: Jul 2005
Posts: 7,571
Likes: 223
Originally Posted by MercenaryFH
oh I see. So....for like "riding" purposes like Im going to be doing, I mean even tho my bike is steel im just curious, but for slight offroad but mostly city riding (assuming u dont get hit by a car/in an accident with your bike) would aluminum hold up over a long time? or eventually fatigue by being just ridden on in the city and kinda break that way?
You shouldn't worry so much about it, it's all in the design of the individual bike. Here's an example of an aluminum framed bike that will hold up to some serious off road abuse:
https://www.intensecycles.com/web/m3.html

And here's a steel framed bike that won't hold up to any off road abuse:
https://www.lemondbikes.com/bikes/roa...eel/sarthe.php

They're both nice bikes in their own way, but obviously it's not about frame material, but about what each is designed for-
well biked is offline  
Reply
Old 09-05-07 | 02:05 AM
  #10  
Bob Dopolina's Avatar
Mr. Dopolina
Titanium Club Membership
15 Anniversary
 
Joined: May 2007
Posts: 10,275
Likes: 184
From: Taiwan

Bikes: KUUPAS, Simpson VR

I used to sell those bike right around the time your model seems to come from. In fact we had one as a shop bike. That thing was beat on by everyone and just kept going. I personally hucked it off a cliff one time and fished it out of a tree (after a serious ejection from the top of a big drop) another time. Trued up the wheels and lent it to someone else the next weekend.

Someones probably still riding it.
Bob Dopolina is offline  
Reply
Old 09-05-07 | 04:53 AM
  #11  
Senior Member
 
Joined: Aug 2005
Posts: 33,657
Likes: 1,119
From: Pittsburgh, PA

Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!

Originally Posted by lebowitz
the problem with aluminum is that is actually can not bend much over time without failing. It can bend very little before deforming permanently (like an aluminum can) and never returning to the original shape. So the failure case is usually one traumatic incident that wrecks it structually.

Steel can bend and be bent back and that is essentially what makes it resilient and desirable as a frame material (along with its vibration absorption property)
You are confusing stiffness (the ability to resist bending) and elastic deformation (stress that doesn't permanantly bend a structure) with ductility (the ability to bend permanantly without failure).

What you are incorrectly describing is "fatigue life" which is how many stress cycles, at a stress level below that needed to permanantly deform the material, a given material will take before it fails.

Steel and Ti, if kept below a stress threshold, have an effectively infinite fatigue life. Aluminum, even at low stress, has a finite fatigue life and will crack sooner or later. That said, the practical life of most aluminum frames is so long that failure is a non-issue unless the frame is badly abused. BTW, you can also ruin a steel frame if you are abusive enough.

To the OP: as the others have said, your frame is a high strength steel and the "butting" means the tubing wall thickness is varied to reduce weight while maintaining strength where needed. It is not aluminum in any way.
HillRider is offline  
Reply
Old 09-05-07 | 08:21 AM
  #12  
Thread Starter
Junior Member
 
Joined: Sep 2007
Posts: 14
Likes: 0
From: Kentucky

Bikes: Giant Sedona (unknown year)

ah indeed it seems to be a VERY nice bike. i'd prolly buy steel more now, but it's so cheap..it makes me thing the bike is poorer quality, like the steel sedona is only like 300$ now, and the aluminum is like 500......lol?
MercenaryFH is offline  
Reply
Old 09-05-07 | 09:33 AM
  #13  
lebowitz's Avatar
Craig A. Lebowitz
 
Joined: Oct 2004
Posts: 372
Likes: 0
From: Washington, DC

Bikes: 1984 Trek 520 | 2002 Specialized Hardrock

Originally Posted by HillRider
You are confusing stiffness (the ability to resist bending) and elastic deformation (stress that doesn't permanantly bend a structure) with ductility (the ability to bend permanantly without failure).

What you are incorrectly describing is "fatigue life" which is how many stress cycles, at a stress level below that needed to permanantly deform the material, a given material will take before it fails.

Steel and Ti, if kept below a stress threshold, have an effectively infinite fatigue life. Aluminum, even at low stress, has a finite fatigue life and will crack sooner or later. That said, the practical life of most aluminum frames is so long that failure is a non-issue unless the frame is badly abused. BTW, you can also ruin a steel frame if you are abusive enough.

To the OP: as the others have said, your frame is a high strength steel and the "butting" means the tubing wall thickness is varied to reduce weight while maintaining strength where needed. It is not aluminum in any way.

thanks for setting me straight
lebowitz is offline  
Reply
Old 09-05-07 | 10:31 AM
  #14  
Thread Starter
Junior Member
 
Joined: Sep 2007
Posts: 14
Likes: 0
From: Kentucky

Bikes: Giant Sedona (unknown year)

i need to get some pics of this bike :-D
MercenaryFH is offline  
Reply
Old 09-05-07 | 12:21 PM
  #15  
Thread Starter
Junior Member
 
Joined: Sep 2007
Posts: 14
Likes: 0
From: Kentucky

Bikes: Giant Sedona (unknown year)

btw how hard are rear derailers to put on, i wouldnt mind upgrading mine, it works fine but ya know
MercenaryFH is offline  
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.