curious about 700cc, 28", 29" diff?

Unicycles and Equipment
1

Hello, I just picked up a 700cc Alex wheel for a guy in my club. I’m wondering about the 28 or 29 inch difference.

This is what I am thinking, please correct me if I’m wrong.

You take your 700cc rim.

You can put a tire like the 700cc Kenda Kwest on it, but you can also put a 29" Nanoraptor on it? Or are there different sizes of rims?

Thanks

2

Hey Sofa. It’s actually 700c, not 700cc.

What counts is the Bead Seat Diameter, or BSD, which for 700c is 622mm. The 29er tires have a BSD of 622. The ISO description of the Nanoraptor is 52-622, which means a width of 52mm and a BSD of 622mm. The IRC Mythos 29er tire is 52-622 also.

In contrast, the 26" Nanoraptor’s ISO designation is 52-559.

The 26", 27", 28" or 29" designation indicates a rough sense of the actual outer diameter of the tire when mounted and inflated.

The 24"x3.0" Gazz’s ISO designation is 75-507.

As far as connecting with the proper rim, there is an assumption that a 24" rim works with a tire with a 507mm BSD, a 26" rim works with a 559, and a 28/29/700c works with a 622.

Tubes are listed as 29x1.9/2.3, or equivalently 700x47/52.

The real life situation is actually a more complex than that, when you throw in road tires and different countries’ conventions, but that should get you through the mountain stuff, which is simpler.

When in doubt, get the ISO designation for the tire, and you should be all set.

3

Re: curious about 700cc, 28", 29" diff?

Hello,

you are right.the fat WTB tyres will fit on the same 700c rims as Lance Armstrongs wheels.

the number 28 should be dropped from this board,it only adds confusion.28 is another size rim diameter compleatly,used on old english 3 or 4 speeds with rod brakes.a WTB 29er tyre will not fit that old size.

4

my understanding is that 700c tires are also designated as 28". Or at least that is what it says on the side of my road “kenda Kwest” tire.

It says “700c X 35c - 28 X 1 5/8 X 1 3/8”

This lead me to believe that i could call my tire a 28", and equally a 700c.

Am i wrong assuming this?

-Ryan

5

thanks everybody. I guess I have the same question as everyone else…why didn’t he just get a Coker?

:smiley:

6

Lots of tire sizes

Take a look at this link: Tires Sizes :sunglasses:
It’s a lot of information about tire sizes, including how to figure if a tire will be compatible with a rim. ISO seems to be the best reference for tire sizes, no differences depending on where you are or what manufacturer.
I don’t remember exactly where I got it from, possibly Sheldon Brown’s web site. :thinking: