Trying to go road tubeless! Fitting Hutchinson Sector 28 tyres

Having real problems getting my front tubeless tyre to seal against the rim 🙁 am I doing something wrong?

I’ve had compatible wheels for a couple of years and when my tyres needed replacing decided to take the plunge and try them out.

After the positive reviews of the newish Hutchinson Sector 28’s, including on road.cc I thought they looked ideal for the rough roads on my commute and the roads around generally.

So, after watching some videos, reading various blogs etc this was my plan of attack.

Fitted tubeless valves with removable core.
Fitted the Sectors – went on easily by hand (wheels are Easton EA90RT’s)
Tried track pump to pop them on in place, this was ok with rear, not on the front.
Resorted to co2 and this worked, quick inflation, crack / snap noise as, presumably, the bead seats in the correct place.
Deflate, remove valve core, squirt in sealant (Hutchinson Protect Air) , re inflate, spin round to spread it out.

Immediately at around 80psi sealant foams out from a few places around the bead edge, Hutchinson instructions say leave for 24 hours so I do that, re-inflate, spin a few times and the same thing happens.

I noted that the road.cc blog had a similar experience, taking a few days to seal so I left them and re’inflated for a day or so with no success, loosing half the psi over night.

So this weekend I decided to try again from scratch, removing all the sealant and popping them back on with a co2 cartridge and this time trying some Caffelatex sealant instead. Perhaps a little less immediate loss of air and foaming sealant from around the rim, I actually managed a 45 min ride with ok’ish pressure but after about 8 hours it’s down to 20-30psi from 85 starting point.

Now that all points to the bead not sealing / sitting in the right place but as it snaps and cracks in how do you know if it’s in all the way around properly? Deflating and inspecting the bead / rim, it all looks ok to me, the tyre looks attached to the rim and different to a standard clincher.

I don’t have a compressor to try it again.

The rear tyre goes from 85 psi to about 78 over night so that’s not ‘leave it for weeks’ perfect but ok, I always check tyres before riding anyway.

Anyone have any advice or experience of Easton Tubeless wheels or Sector 28’s fitting? I’m reluctant to give up and fit a tube but it’s looking like that will be the outcome.