Is anyone using the folding BBs tubeless? They don’t seem to claim to be TLR/TLE, but do they work OK without the tubes?

I haven’t used those but I’ve converted a lot of standard tyres to tubeless over the years using liquid latex and split inner tubes. Results vary, it often takes a week or more for the sidewalls to seal properly – you can see the sealant oozing through the pores in the rubber. Basically, you just pump them up and ride it round the block, then leave it overnight. Keep repeating that until it stays inflated overnight. Usually only takes one or two inflations, but I’ve had them take a week or so to seal up enough to be useful. Just not really worth the hassle now that you can buy proper tubeless tyres.

I have a set on my DJ bike and I wouldn’t want them tubeless, what is the rational?

Same as @nwgiles I have them on my DJ bike pumped up hard on tubes.
Not sure of reason for going tubeless?

My experience of non tubeless Schwalbe tyres in the past wasn’t good, they leaked so much that no amount of sealant would help

Got them tubeless on the pump track bike. Fine on the front, but the rear one won’t hold enough air for much longer than a day or two. Seals fine but won’t stay up. Not an issue as the bike doesn’t get used that often and pumping it up before a ride isn’t a huge faff TBH.

Had a set of these on the ebike commuter thingy I built for a bit…

They worked Tubeless perfectly fine for me.. Just a single wrap of tesa tape and orange seal endurance. :)

Thanks all.