How do I choose the correct width of the tubeless tape that I need for my wheels?
We need to measure our rim exactly:
The rim tape should be positioned like this, covering the entire bottom of our rim:
If the rim tape is narrower than the rim itself, it will be a guarantee of future problems.:
And if the tubeless tape is wider than the bottom of our rim, it is also a guarantee of future problems:
Now we understand how the tubeless tape should optimally fit our rim, to choose the optimum width tape:
Dismount your front wheel (easier to dismount than the back wheel) and remove air pressure and tire. Check that the standard rim tape completely covers the bottom of the rim. If so, then remove the standard rim tape, place it on a flat surface and measure it. This is the correct size you must choose for your tubeless tape or the closest possible.
If you would take measures on the rim, without removing it previously, as the rim is concave, then the measurement size of the rim tape will not be correct.
And if the standard rim tape that your bike had as standard does not completely cover the bottom of the rim, you will have to add those missing millimeters to the obtained size.
If your wheel does not have a rim tape as standard, then cut a piece of paper (as a piece of rim tape) of the width that you think fits and place it on your rim, adapting it to its concavity, so you can check if it fits correctly or if you need a little wider or narrower width. Cut pieces of paper till you find the right size piece that fits your rim, and measure the size.