Front derailleur clamp diameter
#1
tabula rasa
Thread Starter
Join Date: Sep 2004
Location: brooklyn, ny
Posts: 361
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Front derailleur clamp diameter
i want to buy a new compact front derailleur for my lemond sarthe but i'm not sure what clamp diameter i need. is it 31.8 or 35. thanks.
#2
Senior Member
Join Date: Mar 2007
Location: Louisville, KY
Posts: 469
Bikes: Trek Madone 5.5, Klein Q Pro Elite, Surley LHT
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
measure the diameter of the seat tube in the area where the derailler will be mounted. Better yet look at the current derailleur and use the same size. My guess is that you have a 31.8 clamp size.
#3
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,096 Times
in
742 Posts
Your current derailleur should have the diameter stamped on the inside of the clamp or the braze-on adapter clamp. BTW, 31.8 mm is 1-1/4" and 35 mm (actually 34.9) is 1-3/8" so measuring with a ruler or calipers should be fairly simple.