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I have a mountain bike with a 26 X 1.95 tire. I need a replacement front rim for the tire. What size rim do I need?

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  • Aside - What happened to your rim such that the tyre is still okay ?
    – Criggie
    Commented Jan 20, 2023 at 22:19

2 Answers 2

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(Note that this info will get you the correct rim, but if you are replacing the whole wheel, there a few other considerations to make to ensure compatibility with your bike, such as brake and axle type)

Bike tire sizes can be a bit complicated. When we hear tire sizes like 26" or 29" what that's really referring to is the approximate outer diameter of the tire overall. What you really need to know to make sure your tire will fit on a rim is the bead seat diameter (BSD) which is the diameter of the part of the tire where it actually mounts on the rim.

There are many different rim diameters out there, though there are a few common standards that are used much more prevalently than the others. Fortunately this information is printed right on the tire in an ISO notation of {tire width}-{bead seat diameter}. Your tire says "26x1.95" on the side, but somewhere more subtly, perhaps next to the tire pressure recommendation, there should be something printed that says something like 50-559 meaning it can only be mounted on a rim with a diameter of 559mm. If you need to replace the whole wheel and tire because it was stolen, you can reference the back tire, assuming your front and back wheels are the same size (as they are almost always, looking at you, Terry Bikes).

When matching a tire with a rim, you must also consider width -- if you put a tire on a rim that is too narrow or too wide, the tire may pinch, blow off, or otherwise not handle properly. There are general guidelines about the proper tire width/rim width ratio, but it's best to check with the manufacturer. Also worth noting that while matching the diameter of the tire/rim is absolutely necessary, there is a range of widths which will be suitable for a given tire. For example, looking at Schwalbe's spec a 1.95" (50mm) tire should be mounted on rims from 17 to 30mm with 23mm falling right in the center of that range.

For a standard 26x1.95" tire (it says 50-599 on the side), you would need a 599mm diameter rim, with 23mm being the sweet spot for width.

More about tire sizing at Sheldon Brown's website

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Presuming you want to rebuild the existing wheel with a new rim:

You need a 26" rim with the same spoke count as the old one. The number of spokes will probably be one of 28/32/36.

If you had rim brakes, the new rim needs a rim brake track. Modern disk brake bikes don't need a track for brakes around the edge.

The BSD (Bead Seat Diameter) needs to be 559mm unless your tyre has a subtly different number written on the sidewall. There are a bunch of different 26" sizes, but 559 represents the vast majority.

If you're lucky, the existing spokes+nipples are all undamaged and reusable. AND they are a suitable length for the new rim. Otherwise you will need to replace all the spokes too.


Pricewise it may be better to simply purchase a complete replacement front wheel. The requirements that carry over inclide a rim-brake track or a disk rotor mount to suit your existing, but the number of spokes may be different.

You will need to make sure the axle mounting method is the same. For a 26" wheel it will be either a Quick Release or threadded on axle nuts. A "Through Axle" is unlikely to fit your existing fork dropouts.


Aside - What happened to your rim such that the tyre is still okay ?

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