Because I'm not feeling the love!
Brand new Stans Crest ZTR rims on Hope hubs, Nobby Nic Evo Pacestar 2.1's - surely the tightest tyre rim combination known to man. I've mounted some tough combinations, but this is the worst by far. Yes I tried all the usual tricks of pushing the bead into the well all the way round, unseating the valve stem. I even managed to snap a Park tyre lever!
Anyway after much cursing I put a tube in and inflated to seat the tyre - noticed it was on backwards and remounted one side with a generic tubeless valve. Struggled with the tyre again and remounted second bead. Then sprayed the soapy water and pumped. But the tyre simply will not seal around the valve.
Are the crest rims too narrow and require Stans specific valves that go down into the drilled valve hole? Is he green Hope rime tape not airtight? Looks OK to me. Are the beads so tight that a track pump can't give a big enough push to push the beads out and mount the tyre? It seated fine with a tube, so it WILL fit! I tried a CO2 canister, just for fun, but even that didn't give enough pressure.
Would welcome any advice - specifically to this combination.