I have got an air leak between the rim and tyre, you can see small bubbles at the rim/tyre interface. It is enough for one tyre to go down 20 psi and another to go almost completely flat overnight. The rims are stans flow with tape and rim strip and the tyre are standard kevlar Kenda Nevegal. Both tyres are seated well into the rims and it looks like the bead is seated okay. I have used about 200ml of sealant into both tyres and i have rotated, left on side and gone for a short ride etc.
SO i am out of ideas, my next step was to take the tyre and rim strip off and put a couple of extra layers of tape on the rim. Probably electrical tape rather than the stans stuff, the aim would be to get a tighter fit between tyre and rim. Good idea? Also can i reuse the stans sealant that is in the tyres already?