Planning to upgrade my 26″ MTB wheelset. Should I choose 650b instead of 26″ for the upgrade?

I am running a pair of Mavic Crossone with Schwalbe 2.1″ Big Apple. Will upgrade to a custom build – Hope Pro4 hubs, 32 spokes, Stan Crest Aluminum rims. Preferred tyre will be schwalbe Marathon Supreme 1.6″. I mainly do XC, touring and trekking on half/half hilly/flat areas, kind of 50% paved surface, 25% badly maintained concrete road, 5% off road, the rest are mix of gravel or sandy trails.

I checked with the bike manufacturer, both my frame and the fox performance 100mm travel air fork will accept 650b with 1.6″ tire on. The 650b wheel+tyre diameter will be 12mm longer, circumference will be roughly extended by 2% compared to my current 26″ setup. The bb will be 6mm higher than I currently have.

I know 26″->650b is an endless debate. But I will upgrade my wheelset any way. The price tag for 26″/650b upgrades are almost the same. Should I choose 650b for better roller-over, curb hopping ability, potentially more comfortable ride (650b tyre holds more air), in the expense of 200g heavier set up, 6mm higher bb?

Wouldn’t have thought a 1.6″ 650 tyre would hold as much air as a 2.1″ 26″ tyre?

Should I choose 650b for better roller-over,

only 1 mm in it.

EDIT

The 650b wheel+tyre diameter will be 12mm longer, circumference will be roughly extended by 2% compared to my current 26″ setup.

you sure? i got different numbers?

584 + 2 x 42 = 668
559 + 2 x 55 = 669

You’ve still got more choice in 26 atm.
I can’t really see 26 stuff being that hard to find for a while yet.

Been through this myself recently, with a new bike and a rebuild of an old faithful.
Both frames could take 650b with smaller tyres.

Sticking with 26 because I like big tyres, on and off road and I don’t see any point in limiting choice and changing for the sake of it.

The 2.00 Marathon Supremes are great btw.
🙂

1.6″? Eh? bugger that.