NoTubes UST valve help please!

Hi,

Im trying tubeless out and thought it was going alright however i have a leak around the valve. Do the notubes valve stems work by tightening the small nut on the outside of the rim to gain a seal? Or is there something else i need to do?
The tighter i do the nut the less air comes out however i cant do it tight enough so that no air comes out! Im using mavic crossmax rims, with stans sealent.

Thanks

have you put the little rubber gromit in there?

Nope, all i got in the packet was a valve and plastic cap.

Like this

The eclipse system has a rubber washer between the rim and the locknut to seal it. Failing that try some silicone sealant.

Are you using a Rim tape or the rim strip ?

Thanks Sandwhich, I will see if i can find something to do that.

Offroading, niether because they are UST rims which only have the spokes going through 1 rim wall so there is an air tight surface to mount the rim onto.

OK. Are they leaking alot or just a bit ?

Have you tried letting the sealent pool in the tyre below the valve then shaking the tyre back and forth so the sealant slashes around – it should seal the gap over the valve stem.

I gather your are using the proper Valve too as there are different ones…