29" rims

Are all 29" rims the same width? Is the KH29 the same width as the skinny rim on the Yuni 29er and if they are different what are the measurements or where can I find the widths…

There aren’t any 29" rims. Only 29" tyres. And they all fit on rims designed for 28" tyres. The 29" tyres are just a little fatter.

Strictly speaking this isn’t quite true. Modern 28" and 29" rims have the same tyre bead diameter, which is called 700c, so all 700c/28"/29" tyres can fit on them.

However, there are 29" specific rims, like the KH and Nimbus rims, which are significantly wider, like 2 times wider than other 700c rims. I think Bontrager make one too. Whilst you can fit all tyres on all rim widths, running a narrow road tyre (like 1 inch or below), on a 29" rim would be asking for trouble, and running a wide tyre like a big apple or a muni 29" tyre on a narrow rim isn’t nice either. The super-wide KH rim makes a real big difference to how stable the wide tyre feels, which is really important on a unicycle, much more so than on a bike, as you put more sideways forces on it.

I’ve also got 26x1" slicks on my bike which has some cheap rim designed for 26x1.75"-2.1" tyres, and it was awfully hard to get the tyres to seat in the rim, and they look a bit too spread out (seem to work though).

To answer the original question, if the Yuni rim is what’s called the Nimbus rim in the UK, then it’s similarly wide to the KH, but I presume must be a different rim, as it needs different length spokes according to the spoke calculator.


I realize the 28/29 rim issue, sorry for not being specific enough. What i have now is a Yuni 29 with a nanoraptor tyre and it often feels like I could roll it off the rim so I was wondering if the KH29 rim is wider or does it have the same issue

Can you fit a schawble big apple 28 x 2.35 on a KH 700c??

I guess yes, is that rigth?

Thanks guys!

KH rim is 36mm wide on the outside, 30.8mm on the inside. It looks super-duper fat compared to most 700c rims.

I think there was an old (narrow) and a new (wide - 36mm outside) nimbus rim, so it might be worth measuring yours to see how fat it is.

If you’ve got the fat rim, it might be a tyre pressure issue. Otherwise, if you’ve got a narrow rim, a wider rim makes this rolling thing much less likely.

monociclos - yes you can.


Thanks My existing rim is a Mavic MA40 and it reads 622x13-6106 on label any idea how this translates?

MA40’s are skinny for a 29er tyre…the kh rims are about twice as wide…i have 2 of them, pm me if you cant source one and i’ll sell one to you…shipping is expense though since it classified as “oversized” by UPS

It has often been discussed here that the Schwalbe Big Apple has a tendency to steer to the sides of the road (depending on road conditions, tire pressure, rider abilities).

Has anybody some experience how rim width influences this behaviour?


My 29er rim is a Mavic T224
I use it for muni and also have the problem of tire roll. Are these rims wide or narrow compaired with the KH?
I think it’s a touring bike rim. Whatever that means!

Most of the mavic touring rims are something like 23mm outer width. I think the widest one is 24mm. So the KH rim at 36mm is more than half as wide again.

I didn’t notice the tyre roll happening on the KH rim at all, even with sidehops and a not too hard tyre. Previously I had to use more pressure than I liked in order to avoid tyre roll.


When i look closer on my rim, it says “28mm” and “37mm” on top of each other. What would these be refering to? When i meausure it with a ruler it only comes to about 25mm.

Might be a recommended tyre size range. My 26" bike rim I’ve got here says 1.75"-2.1" on it, and it came with 1.75" tyres on.


I’m sure that’s right. I’ve got Mavic 224s on my road bike* and they do recommend minimum 28mm tyres on those.


  • OK, before you say I’m weird running 28mm tyres on a road bike… It’s a fast touring frame built for 32mm tyres that I don’t use for touring anymore, so it’s become more of a commuting/Audax bike (so 25mm would be more normal) - but anything narrower than 28mm looks ridiculous with the frame clearances.