Wheel diameter with different tires

Now that I have a bike project underway involving disc brakes and decent clearances, I sat down and did with a purpose something I’d done a couple times just for fun: figured out tires for 700c, 650B and 26″ rims that give equivalent wheel diameters*.

Now it’s inscribed in the immutable internet, and I can refer back to it later.

Narrower. In my circles, the 42mm 650B “Hetre” is the most-hyped tire… well, ever. I’ve never ridden it. Of these first three, the 2.1″ mtb tire is the only one I’ve ridden, and I’ve worn them bald. It’s a good size. I’ve also ridden a 590×37, which has a similar OD to the 650B, (and can be boughten or ordered at any LBS). It was also a good size, for the bike it was on.

559 (26″ mtb) 584 (650B/27.5″) 622 (700C)
53mm 42mm 23mm
53mm 42mm 23mm
665mm OD 668mm OD 668mm OD
2.1″ MTB 42mm 650B 23mm 700C

Plumper. I’ve only ridden the 32mm tire. Good for everything but deep gravel, which is just sucky no matter what.

559 (26″ mtb) 584 (650B/27.5″) 622 (700C)
63mm 50mm 32mm
63mm 50mm 32mm
685mm OD 684mm OD 686mm OD
2.5″ MTB 2″ 27-five 32mm 700C

I do not know of anyone who’s actually set up a bike with interchangeable wheelsets in different sizes, but it must’ve been done. It’s probably common in some circles.

* The rolling diameter is important-ish, because a big mismatch can affect the handling, standover, pedal clearance, etc. I’ve happily and comfortably run 25s through 40s on my Quickbeam, but that’s the best bike in the world and can do anything.

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UI/UX Designer, bike nerd, artist.

5 thoughts on “Wheel diameter with different tires”

  1. I like the idea of a multiple wheel size bike, although it may mean more complexity and expense. It would be a great way to compare the effects of wheel size in a real world feel way.

  2. Philip, basically what I have now… 700X31C and 650X47B. Very different feel on the road (700C wins!) and on dirt (650B wins!). I was planning on going straight over to the B wheelset full time, but may keep both built up and available as they’re so different.

  3. Are the rim widths the same? The guy at the shop thought my Marathons should feel better than the Big Apples because “the rims are so narrow.” 24mm rims do seem skinny on 60mm tires. Maybe wider rims on the 650B set would make them feel better on the road?
    Or keep doing what’s workin’…

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