I'd tried a couple of times to go tubeless on my 29er but the combination of rims and tyres just weren't having it, so over the summer I bought myself a pair of Halo Vapour rims in a very fetching red.
Last week I finally got round to building them up. The front went fine and after a few repeats pump, ride and pump again the tyre is now holding pressure. The rear has been a little less straightforward.
The DMR singlespeed hub I used has always given a narrow clearance between the spokes and the brake caliper and when I span the new build on the bike it became clear that the change of rim and spokes from plain gauge to double butted had reduced that clearance to nothing. It also became clear that the tyre was not holding pressure for more than ten minutes or so. Lots of shaking, spinning and pumping failed to make it much better but a bowl of water showed that the sidewalls were porous in places. Tipping the wheel on it's side to spin it seemed to help and then it was time to tackle the lack of caliper clearance. I found some Shimano tab washers to put between the disc and hub, put the wheel in a stand and turned to my toolbox.
I looked down and as the fog of tubeless jizz cleared from round the wheel and my right knee I could see that the tyre had popped off the rim. I put it back but the tyre would then only partially pump up and was very distorted. It appears that the bead had snapped within the casing. For the record the tyre was a four year old Schwalbe Albert, only lightly used and only pumped to 45psi to get it to seat. To get the bike back together I had to fit the old worn out tyre and tube and guess what? Taking it off at the start of this debacle must have disturbed a thorn or something because it went straight down and I had to fit another tube.
A new tubeless ready tyre is now on order.