Go Back  Bike Forums > Bike Forums > General Cycling Discussion
Reload this Page >

Can I mount 25mm tires on a rim designed for 26mm tires?

Notices
General Cycling Discussion Have a cycling related question or comment that doesn't fit in one of the other specialty forums? Drop on in and post in here! When possible, please select the forum above that most fits your post!

Can I mount 25mm tires on a rim designed for 26mm tires?

Old 06-23-20, 12:16 AM
  #1  
SpeedyBlueBiker
Senior Member
Thread Starter
 
Join Date: Nov 2018
Location: Redmond, WA & Bangkok, Thailand
Posts: 88

Bikes: 1999 Giant ATX MTB, 2002 Lemond Zurich, 2018 Fuji Transonic 2.3, 2019 Specialized Tarmac Disc Expert

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Liked 14 Times in 13 Posts
Can I mount 25mm tires on a rim designed for 26mm tires?

I've got about 3,300 miles on my road bike tires. It's the tires the bike came with when I bought the bike. They are 26mm tires mounted on carbon rims. When I started looking for 26mm tires there weren't many choices but a lot of choices for 25mm. Could I mount 25mm tires on the same rims or would this not work?
SpeedyBlueBiker is offline  
Old 06-23-20, 12:22 AM
  #2  
caloso
Senior Member
 
caloso's Avatar
 
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 39,210

Bikes: Ridley Excalibur, Gazelle Champion Mondial, On-One Pompino, Specialized Rock Hopper

Mentioned: 62 Post(s)
Tagged: 0 Thread(s)
Quoted: 2311 Post(s)
Liked 1,095 Times in 576 Posts
Yes.
caloso is offline  
Likes For caloso:
Old 06-23-20, 12:49 AM
  #3  
sledgefisher
Member
 
Join Date: Jun 2020
Location: Te Kuiti, New Zealand
Posts: 35

Bikes: 1968 - Peugeot PR10 1987 Bianchi Brava, 1987 / 1987 Gitane Super Corsa Reynolds 531, 1969 Moulton Super, 2020 Kona Dew Deluxe

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Liked 15 Times in 10 Posts
Yes is the answer. If you were looking for more information on wheel & tYre sizes Sheldon Brown's website is the place to visit.
sledgefisher is offline  
Likes For sledgefisher:
Old 06-23-20, 08:25 AM
  #4  
wgscott
Occam's Rotor
 
wgscott's Avatar
 
Join Date: Jul 2013
Posts: 6,300
Mentioned: 61 Post(s)
Tagged: 0 Thread(s)
Quoted: 2366 Post(s)
Liked 1,410 Times in 719 Posts
Sounds too risky.

Seriously, I think tire width tolerances are greater than 1mm. You will be fine.

But if it were me, I would be asking how wide a tire I could mount.
wgscott is offline  
Likes For wgscott:
Old 06-23-20, 08:30 AM
  #5  
aclinjury
Senior Member
 
Join Date: May 2013
Posts: 475
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 359 Post(s)
Liked 101 Times in 76 Posts
what's the INTERNAL width of the rim?
aclinjury is offline  
Old 06-23-20, 09:25 AM
  #6  
Rides4Beer
Senior Member
 
Join Date: Oct 2018
Location: SC
Posts: 1,164

Bikes: Giant Revolt

Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 594 Post(s)
Liked 537 Times in 293 Posts
Yes, but as mentioned, I'd be looking to go bigger if they'll fit the frame.
Rides4Beer is offline  
Likes For Rides4Beer:
Old 06-23-20, 10:14 AM
  #7  
Ross520
Senior Member
 
Join Date: Aug 2019
Posts: 316
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 173 Post(s)
Liked 171 Times in 99 Posts
Originally Posted by SpeedyBlueBiker View Post
I've got about 3,300 miles on my road bike tires. It's the tires the bike came with when I bought the bike. They are 26mm tires mounted on carbon rims. When I started looking for 26mm tires there weren't many choices but a lot of choices for 25mm. Could I mount 25mm tires on the same rims or would this not work?
As others have suggested, I think it would be advantageous to go UP a size rather than down. 28s will be quicker, as well as more comfortable. They're not any more expensive, either, so it's really a no-brainer unless they physically will not fit.
Ross520 is offline  
Likes For Ross520:
Old 06-23-20, 10:20 AM
  #8  
COYSpurs
Junior Member
 
Join Date: Jun 2020
Posts: 14
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Should be able to. I would just contact the company that makes the rims and ask. It will vary.
COYSpurs is offline  
Likes For COYSpurs:
Old 06-23-20, 10:29 AM
  #9  
ofajen
Cheerfully low end
 
Join Date: Jun 2020
Posts: 357
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 98 Post(s)
Liked 156 Times in 97 Posts
FYI, here is a version of the ETRTO compatibility chart. I regard it as conservative and I’m guilty of going a bit wider.

https://bikerumor-wpengine.netdna-ss...ards-chart.gif

Note that the difference of 25mm to 26 mm doesn’t even register on the resolution of the chart. It’s a small difference.
Otto
ofajen is offline  
Likes For ofajen:
Old 06-23-20, 10:34 AM
  #10  
ClydeClydeson
Senior Member
 
Join Date: Mar 2019
Posts: 186
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 53 Post(s)
Liked 57 Times in 43 Posts
100% it will work.

The only two things to look out for are that the tire is at least a wee bit wider than the rim, and that the tire mounted on the rim will fit in the frame or fork. Going down one mm in width will be totally fine.

As mentioned above, you can also choose to go up in width - any tire labelled '700 X <width>c' or '622' can be mounted on your rim, but you will be limited by the tire clearance in your frame and fork.
ClydeClydeson is offline  
Likes For ClydeClydeson:
Old 06-23-20, 11:00 AM
  #11  
Phil_gretz
Journeyman Bike Commuter
 
Phil_gretz's Avatar
 
Join Date: Aug 2009
Location: Alexandria, VA
Posts: 5,913

Bikes: '71 Jeunet 640, '74 Fuji Special Road Racer, '79 Peugeot PXN10LE, '88 Fuji Saratoga, '13 Motobecane Fantom29 HT, '16 Motobecane Turino Pro Disc, '16 Motobecane Gran Premio Elite, '18 Velobuild VB-R-022

Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 983 Post(s)
Liked 638 Times in 362 Posts
Originally Posted by ClydeClydeson View Post
... but you will be limited by the tire clearance in your brake calipers (if not a disc bike).
Could also be the limiting factor...
Phil_gretz is offline  
Likes For Phil_gretz:
Old 06-23-20, 11:03 AM
  #12  
ljsense
Senior Member
 
ljsense's Avatar
 
Join Date: Sep 2009
Location: Madison, Wis.
Posts: 640
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 211 Post(s)
Liked 83 Times in 47 Posts
Originally Posted by COYSpurs View Post
Should be able to. I would just contact the company that makes the rims and ask. It will vary.
No, do not do this. It will not vary. There is no rim that will fit a 700x26 that will not fit a 700x25. You can also fit a 700x23 and, as others have suggested, a 700x28 if the larger tires do not rub against your fork or frame.
ljsense is offline  
Old 06-23-20, 04:39 PM
  #13  
caloso
Senior Member
 
caloso's Avatar
 
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 39,210

Bikes: Ridley Excalibur, Gazelle Champion Mondial, On-One Pompino, Specialized Rock Hopper

Mentioned: 62 Post(s)
Tagged: 0 Thread(s)
Quoted: 2311 Post(s)
Liked 1,095 Times in 576 Posts
1) Actual widths vary widely compared to the width printed on the sidewalls.
2) Some BF posters would be shocked at how cyclists in the real world (CX'ers in particular) exceed recommended width limits
caloso is offline  
Likes For caloso:
Old 06-23-20, 09:46 PM
  #14  
Ross520
Senior Member
 
Join Date: Aug 2019
Posts: 316
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 173 Post(s)
Liked 171 Times in 99 Posts
Originally Posted by caloso View Post
1) Actual widths vary widely compared to the width printed on the sidewalls.
2) Some BF posters would be shocked at how cyclists in the real world (CX'ers in particular) exceed recommended width limits
If you read the rest of the those posts you'll see that they're just being facetious. 😁
Ross520 is offline  
Old 06-25-20, 07:20 PM
  #15  
ramzilla
Senior Member
 
ramzilla's Avatar
 
Join Date: Dec 2014
Location: Fernandina Beach FL
Posts: 3,302

Bikes: Vintage Japanese Bicycles, Tange, Ishiwata, Kuwahara

Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 637 Post(s)
Liked 215 Times in 172 Posts
yes, no worries
ramzilla is online now  
Likes For ramzilla:

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 - Do Not Sell My Personal Information -

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