Right finally got my new minion rear dual ply to mount (sort of) on an 819 ust rim. Used a tube to get one side mounted and after removing tube/adding tubeless valve I can pump a track pump like a loon and the second side starts to mount on the rim but never gets up to a proper pressure and pops off the rim when I stop pumping. Tyre maybe gets up to 10-15psi, there seems to be too much air loss from around the vertical ribs on the tyre (raised line of rubber that goes down to the bead maybe ten of them in total around the tyre) Any ideas? Do i try to cut these ribs off or just put some sealent in and try again? I'm worried the sealent will just spray out everywhere tho.
After previous failures/sealent waste I use a removeable core valve, make sure the tyre mounts properly then add sealent later, not sure what to do about this one.