Does this ever work out ok?

Cheers

For a very narrow definition of B+ it might.

It can work

http://singletrackworld.com/forum/topic/650b-and-other-plus-sizes-if-you-like-rim-tyre-frame-fork-combinations

2.8NN’s on 45mm rims cleared through a standard revelation with about 4-5mm each side.

but add in a bit of mud and some wheel flex and they rubbed quite a bit.

gone back to 29.

3 inch nobby nic on 35mm rims in my 36s worked decently. It didn’t have huge mud clearance but it wasn’t so different to what you get with some standard fork/tyre combos. It’d not be your choice if you were building a full time plus bike but I was happy enough.

OTOH, for me the sticky muddy conditions where the clearance would be an issue, are conditions where I’d want to be on a 29er anyway, not on plus. YMMV there. I never got to try it in snow, that could have been a dealbreaker

I’ve got 3″ Bridgers in a 2014 Fox 34 29er. Clearance is a little close at the lower seal bulges but it doesn’t rub. They’re on 30mm internal rims.

I hear that the more recent non-boost fox 36’s have a lot of clearance in 27.5 and 29 flavour.

3 inch Purgatorys on 30mm rims, in a 29″ Pike here. Lots of clearance above the tyres, not too much either side but I don’t really ride in thick mud so it’s not really a problem for me…

[url=https://flic.kr/p/JA7vwy]Tyre rub[/url] by Metalheart-UK, on Flickr

After only ~10 hours use in the dusty dry (mostly)

My Dt Swiss single shot XMM have enough room for a 27.5 FBN 3.25 on a dually rim with loads of room. I’ve actually ridden them with a 29er 3.0 dirt wizard on a rabbit hole, no rubbing, but a bit close for comfort.

Ran a 3″ WTB bridger in a 29er DT OPM fork for ‘project High Fatitude’ no problem, bags of room, no buzz whatsoever.

I’m running a 2.8 Rekon on a 30mm internal rim in a standard Pike. No clearance issues, I’ve even got room for a mudhugger in there. Tried a 3.0 Vittoria Bomboloni but that was a bit tight.