Yes, it was TL ready and mounted tubeless.
I do not have these tires anymore, one had to be replaced due to a de-lamination between the outer layer and the frame of the tire (there was a kind of blister on the tire) and the second was destroyed by a side wall tear due to a stone.
The Pro-one is actually fragile !
To come back on the benefit of ETRTO406 wheels on the Birdy, I have now two almost identical sets of wheels (same hub Hubsmith front, Hope rear, same CX-ray spokes, same Conti Contact Urban tires, only different rims) in ETRTO349 and ETRTO406, both tires mounted on my rims are about 35mm wide (but the ETRTO406 tire is not as high as the ETRTO349 due to wider 25mm inside rim).
I could keep my mudguards (which aren't the Birdy mudguards) by changing the bolts with flat head bold.
No problem at all for the folding, the folding size is slightly higher, but the difference compared to a Birdy with 50x355 tires is really small and not bigger than a Birdy with original mudguards.
Honestly, there is little difference when riding the Birdy.
For me, the only benefit in putting ETRTO406 wheels on a Birdy is the possibility to mount road race tires like the Pro-one that do not exist in ETRTO355.
So, for the four possible sizes of wheels for the Birdy, the pros and cons are:
- original ETRTO355: wide tires >40mm available, balloon and off-road tires available but few types of tires, no real fast tires (Kojak isn't fast, Panaracer almost impossible to find in ETRTO355).
- Brompton ETRTO349: wide choice of tires of many types available, including the ultra fast Greenspeed Scorcher 40x349 but most tires 35mm wide (Brompton standard width), no balloon tire like the Big Apple, no off-road tires.
- ETRTO406: fast race road tires available but max width 32 (or 35mm on wide rims), not that much types of tires usable (due to width limitation of the frame), of course no balloon or off-road tires usable. I do not think that Scorcher 40x406 will fit, even without mudguards.
- ETRTO369: only one tire really available the Kojak, I do not see any benefit to go for this wheel size !