M8 has a Marin Pine Mtn, that came with Maddux DD40 27.5+, Double Wall, 40mm Inner, Tubeless Ready rims. They wouldn't seal, suspecting the tape was actually tubeless ready, he replaced the rim tape and bought some new stan's values. Trying again there's an obvious air leak around the valve, and we can't see why. Even cranking up the valve nut with pliers isn't sealing them.
If air was getting around the tape, shirely it would be coming out of the spoke holes too? [or maybe it is, but the air leak round the valve is the obviously noisy leak?]
Anyone had similar issues? Are the valves the most likely suspect? Off-hand he's gunna smear the valves with silicon sealant, as someone suggested this may help
This comes up repeatedly. Air will be escaping from the valve hole regardless of where the seal isn't complete.
Most issues I've seen are due to the tape not being stuck down well enough- especially at the overlap (the tape sticks better to the rim than to itself).
What width of tape was used?
No idea what sized tape, not anything really wide looking at it, but assumed we'd have also have obvious leaks round the spokes too, if the tape wasn't sealing.
Double wrap the tape, wider tape (maybe 50mm gorilla?), and try different valves.
On my first tubeless attempt, the stans valves had a very flat rubber bung that wouldn't seal the deep, narrow rim well. Some blu-tac did the job of filling the gap nicely. (silicone seal would work too, if allowed to dry).
assumed we'd have also have obvious leaks round the spokes too, if the tape wasn't sealing.
The rim is hollow. If the rim bed isn't sealed anywhere, it'll leak into the hollow and then escape out of the biggest hole. Nipples do a much better job of sealing than the valve which just has a loose fitting metal valve and a metal washer. So wherever your leak in the rim bed is, it'll always come out of the valve hole.
Split tube & save yourself all this needless hassle.
