Any size tyre for any rim?

Hi all, I was just wondering if it is possible to put a thicker tyre on a unicycle that already comes with a smaller one. Eg. I see a 24" uni for sale that comes with a 1.75" tyre. Can I buy a 2.2" thick tyre and put it on the uni, or is the rim only made for tyres of that size? Thanks in avance.

And to add to Eric’s link, the other question is: will there be enough space under the frame of the uni?

Hi Sebcycle,

if you stay reasonable, it will work. The main concern (as pointed out by Pierrox) is your frame clearance. After that, have fun.
Usually, the frame prevents you from doing too big jumps that would be not good (like installing a 4.0 tire on your learner :stuck_out_tongue: )

My very first unicycle was a club 26 that came with a 1.75 tire. When it got worn out, I got a beefier 2.0 tire that was available at the local bike mart and had a lot of fun.

I have put a thicker tyre on the cheap 20" I started with, which has made it into something like a 22" mini-muni! I really like it. The clearance is all you have to watch, but unless you were going up to some kind of monster tyre, I would think you would be OK.

As a rough guide for best results off road I would measure the outside width of the rim and stick between 1.5 and 2x that width for the tire. Much skinnier and you risk pinch flats, and much wider and you need more pressure to keep the tire stable.

On road and on smooth surfaces you can go further outside these norms and just run higher pressures without any real issues.

Or, just try it…

I fretted about this when I wanted to try a mid-fat (3.25") tire on my fairly narrow (35mm) rim. All the guidelines will tell you that’s a bad combination, but I’ve been running it for about a year without issue.

Interesting. What tire and rim?

You need a few key measurements:

  • Width of your frame where the tire passes through
  • Height from rim to "ceiling" under the fork crown (in other words, how tall can the tire be)
  • Nominal width of the tire you would like to try
Measuring the frame is the easy part, at least if you already have the unicycle. Tire measurements are not so simple. Those width numbers, like 1.75", are general at best. The only way to really know is ask people who have one, or buy one and pump it up. You can get a rough idea if you can handle one in the store, for example, but it's really hard to be sure of actual inflated width because it's based on your particular rim size.

So in answer to your original question, “It depends”. It all comes down to the specifics. Some uni frames have lots of extra room in them, but others, like Freestyle (or generic) frames, might be designed to be compact.

Thanks all for your responses, you have set me on the right track. Cheers.