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

front derailleur clamp size?

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.

front derailleur clamp size?

Old 11-19-02, 02:53 PM
  #1  
Airborne
Sir Crashalot
Thread Starter
 
Airborne's Avatar
 
Join Date: Oct 2002
Location: stuck in the mud and my pedals in Pittsburgh, PA
Posts: 114
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
front derailleur clamp size?

Question: I am replacing the front deraileur on my 2002 Giant Iguana frame with a Shimano LX drlr. I am unsure of the clamp size as it comes in 3 different ones: 28.6 mm, 31.8 mm, and 34.9 mm. I have a 31 mm seatpost, and thats all the info i have. there is no info from the giant homepage, and my lbs (over the phone) didnt know, but guessed 31.8. i think it would be 34.9 with that size seatpost though yes? anyone with any info i'd appreciate it!
Airborne is offline  
Old 11-19-02, 03:26 PM
  #2  
a2psyklnut
Senior Member
 
Join Date: Mar 2000
Location: Parrish, FL
Posts: 7,963

Bikes: Lots

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
At another forum I frequent there is a member that works at Giant. I'll contact him and ask for you. Give me a little while to hear back from him.

In the meantime, rule out the 28.6 that's generally used on older thin diameter steel frames.

You could also just measure the thing if you've got a venier caliper. If not, wait a little and I'll try to find out!

L8R
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "WOW, What a Ride!" - unknown
"Your Bike Sucks" - Sky Yaeger
a2psyklnut is offline  
Old 11-19-02, 03:27 PM
  #3  
a2psyklnut
Senior Member
 
Join Date: Mar 2000
Location: Parrish, FL
Posts: 7,963

Bikes: Lots

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Duh,

Take the existing one off your bike. The size should be stamped on the inside of the clamp!

L8R
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "WOW, What a Ride!" - unknown
"Your Bike Sucks" - Sky Yaeger
a2psyklnut is offline  
Old 11-19-02, 04:42 PM
  #4  
pokey
Senior Member
 
Join Date: Jun 2002
Posts: 1,372
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally posted by a2psyklnut
Duh,

Take the existing one off your bike. The size should be stamped on the inside of the clamp!

L8R
That works,as well as measuring the diamerer, or the circumference and doing the math.
pokey is offline  
Old 11-19-02, 09:01 PM
  #5  
moabrider47
I ride a REAL Schwinn!
 
Join Date: May 2002
Location: NH, USA
Posts: 607

Bikes: Lemond Nevada City (stock), '00 Schwinn Moab 3 (very upgraded)

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Airborne,

Check out the Giant site. There is a link to see the Iguana's geometry as your looking at the general info for it. I believe it gives the diameter of the seat tube in millimeters. As long as this is the measurement at the front derrailleur clamp, you should be able to figure it out with this.

-Moab
moabrider47 is offline  
Old 11-19-02, 10:14 PM
  #6  
Airborne
Sir Crashalot
Thread Starter
 
Airborne's Avatar
 
Join Date: Oct 2002
Location: stuck in the mud and my pedals in Pittsburgh, PA
Posts: 114
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally posted by moabrider47
Airborne,

Check out the Giant site. There is a link to see the Iguana's geometry as your looking at the general info for it. I believe it gives the diameter of the seat tube in millimeters. As long as this is the measurement at the front derrailleur clamp, you should be able to figure it out with this.

-Moab
thanks, but as i stated, nothing is on the site.
Airborne is offline  
Old 11-20-02, 11:59 AM
  #7  
Richard D
Donating member
 
Richard D's Avatar
 
Join Date: Sep 2001
Location: Faversham, Kent, UK
Posts: 1,852
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I haven't an Iguana, but my Giant has a 30.8 seatpost and uses the 34.9 clamp so probably...

Richard
__________________
Currently riding an MTB with a split personality - commuting, touring, riding for the sake of riding, on or off road :)
Richard D is offline  
Old 11-20-02, 01:49 PM
  #8  
Dirtgrinder
Dances with Rocks
 
Dirtgrinder's Avatar
 
Join Date: Apr 2001
Location: Jefferson City, MO
Posts: 1,441
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
This if from Sheldon Brown's site:

1 1/8" (28.6 mm) clamp on. (This is the traditional, standard type for most road bikes and older MTBs.
1 1/4" (31.8 mm) clamp on for mildly oversized seat tubes.
1 3/8" (34.9 mm) clamp on for oversized seat tubes, common on aluminum frames.

Just replaced mine on a Giant XTC NRS 2. It was 34.9.
__________________
If everything seems under control, you're just not going fast enough...

To become a registered member of BikeForums Click Here
Dirtgrinder is offline  
Old 11-21-02, 07:47 AM
  #9  
Airborne
Sir Crashalot
Thread Starter
 
Airborne's Avatar
 
Join Date: Oct 2002
Location: stuck in the mud and my pedals in Pittsburgh, PA
Posts: 114
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
thanks richard and dirt... that is very halpful and sounds on the money!
Airborne is offline  

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


Thread Tools
Search this Thread

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

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.