Can I mount 25mm tires on a rim designed for 26mm tires?
06-23-20, 12:16 AM
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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?
06-23-20, 12:22 AM
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Yes.
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06-23-20, 12:49 AM
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Yes is the answer. If you were looking for more information on wheel & tYre sizes Sheldon Brown's website is the place to visit.
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06-23-20, 08:25 AM
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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.
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.
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06-23-20, 10:14 AM
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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?
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06-23-20, 10:29 AM
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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
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
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06-23-20, 10:34 AM
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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.
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.
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06-23-20, 11:00 AM
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06-23-20, 11:03 AM
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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.
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06-23-20, 04:39 PM
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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
2) Some BF posters would be shocked at how cyclists in the real world (CX'ers in particular) exceed recommended width limits
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