I am trying to fit Mountain King 2.2" tyres to Mavic 319Disc (26") rims using the sliced open 20" tube ghetto tubeless method.
I am struggling to get the tyre to seat on the rim (I don't have a compressor but am using "the 2L fizzy drinks bottle air reservoir method). I also tried a CO2 cylinder. Examination of the problems suggests that the 'backing' circle for the valve makes the tube inflexible and too thick close the valve. It might be impossible to seat it 100% with this issue? And as that is where the air goes in it will never seat?
I am using presta valves (as that is what was in the wheel before I started). However I now believe that there is just an insert in the wheel and I could use Shraders. My presta's don't have removable valve cores - which certainly isn't going to help get air in there.
1. Go and buy a compressor. Seems a bit extreme but might be needed anyway - but is that guaranteed to fix the issue?
2. Switch to Shraeder - are the 'backing circles' around the value usually smaller/more flexible - I've only got one old shraeder tube here (a 26") and it looks a similar diam, but feels thinner at the valve? Do different manufacturers vary?
3. Ditch this ghetto method and get rimstrips etc?
4. Why do we need rubber to come outside the wheel anyway - surely I could trim it inside the bead and then the gunk would seal the tyre direct to the wheel - just like a stans kit conversion?