I'm after some advice on how small a tyre I could fit to my Flow (non EX) rims? Preferably tubeless but if I could go considerably thinner using tubes I'd be happy to. The inner rim width is 21.6mm and I'd preferably like to mount tires about 32-35c in size?

I'm using 19mm internal rims on two bikes, they're happy down to 25mm with Conti Gatorskins, but with tubes. 32s should be fine I would've thought.

Ben, I've just put some 40c tyres on my Flow EX rims and they come up fine.

If your rims are 4mm narrower so imagine you'd get away with 35c tyres. 32c may be a bit of a struggle.

See here mate - http://www.schwalbe.com/gb/reifenmasse.html

Plus a bit more here - http://forums.mtbr.com/wheels-tires/min ... 86799.html