Herzlos

I'm trying to fit a Joes No Flats kit (https://www.wiggle.co.uk/joes-no-fla...it-eco-sealant) onto Merida Comp TR (https://www.merida-bikes.com/en-gb/b.../big-trail-400) for the first time.

I've wrapped the tape twice, with the overlap, so the valve has 4 layers of tape.
When I'm fitting it, the hole for the valve is the width of the valve, so the silicon seal block doesn't seem to wedge into the gap.
When filling the tyre with air, I'm hearing/feeling a lot of air coming out around the outside of the valve, so I don't think it's seating well. I can't tighten the valve into the hole further.
I can pump it up to about 20psi using a fairly basic floor pump (not a high volume tubeless), and it'll deflate from that 20psi within a few minutes.

So have I just made a mess of putting the hole in the tape for the valve, or would I expect this to happen and for the sealant to fix it later?

Barry2 

Where the valve goes through the inside of the rim, that part of the rim has a different profile (curve) depending on the Manufacturer and wheel model.
It's far better to purchase the valve from your wheel manufacturer for the actual model you have.

Opting for a universal valve, may work fine, or not!

Barry

alcjphil

Air hissing out at the valve doesn't necessarily mean that the valve isn't seated well at the rim bed. If your tape job isn't well done air can escape at any spoke hole and then will follow the path of least resistance to the valve stem where it will leak out.

Herzlos

So my best bet it to just to redo the entire tape and see if that helps?

frankenmike 

My first tact would be to just keep re-inflating and spinning, see if the sealant eventually fills the gaps.

alcjphil

Your best bet is to closely examine your tape job to see if there is a possibility that there is a gap somewhere. Check your work