31.8 QR Seat Post Clamp
02-07-18, 07:08 PM
#1
Senior Member
Thread Starter
31.8 QR Seat Post Clamp
If my seat-post is 31.6 would a 31.8 sp clamp be the correct size?
02-07-18, 07:45 PM
#2
Senior Member
Join Date: Feb 2012
Location: Rochester, NY
Posts: 17,123
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3790 Post(s)
Liked 2,938 Times
in
1,799 Posts
What are you trying to clamp? If it's the seat tube to secure the post inside, then you want the OD of the top section of the seat tube. Right where the clamp would slide over, differences in clamps' labeled size of about .2mm is common. If you're clamping something to the 31.6mm post then a 31.8mm clamp will likely work. Not sure I answered the real question. Andy
02-08-18, 06:04 AM
#3
Senior Member
Join Date: Oct 2007
Location: West Yorkshire, United Kingdom
Posts: 5,754
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 441 Post(s)
Liked 93 Times
in
79 Posts
Originally Posted by koolerb
If my seat-post is 31.6 would a 31.8 sp clamp be the correct size?
02-08-18, 01:38 PM
#4
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,540
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: 1964 Post(s)
Likes: 0
Liked 979 Times
in
676 Posts
As noted, it's not the seat post diameter you have to match, it's the seat tube outside diameter.
02-08-18, 07:59 PM
#5
Senior Member
Thread Starter
That makes sense. Tube thickness will vary. The OD of the un-clamped seat tube is roughly 34.6. Glad I asked.
