Curious to see a side by side comparison of height and width.
I know some of those running Stooge frames are running 3.8" 27.5 tyres so know they are out there.
I'm guessing they should be taller ......
IIRC height is the same to within 1 mm
27.5 x 3.8? That's obviously taller than 26 x 4, but who is making them?
Hmm.
Do you run this combo?
My apologies it was 26 x 4.7
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Ha!
Bontrager Hodag 27.5 x 3.8
Hmm.
It's actually quite clever, in some ways- I put 4.8s in my bike designed for 4.0s and obviously it raises the bike and BB. Doesn't bother me, it still rides fine but this way you can vary tyre size without varying tyre height. If you're made of money and want to buy extra wheels, anyway. But it increases choice.
But Trek are Trek so inevitably when they saw a settled standard had to attack it, so now they're doing 27.5 x 4.5.
I 27.5 3.8 dune on the horizon northwind?;)
Nah, tbh I know on paper the 4.8s have made it taller and I shouldn't like that, but I've never really noticed 😆
The difference won't be exactly what the maths says, tyre profiles vary as do pressures, a 26 x 4.8 probably "sags" more.
FWIW, all the original Surly 26 x 4" tyres were really 3.8s.
And my 27.5 x 3.5" FatBnimbles really measure 3".
I'd not be going off any manufacturers marketing dimensions.
Aye, tyre companies do like their rubber rulers.
Size will depend a lot on rim width.