Better Tubeless Valve Stems (Bicycle)?

I just mounted up a Schwalbe Nobby Nic on the front of my Hei Hei (which was a wrestling match like I've never had with a tire, including a year as a mechanic), and to my chagrin, once again I'm having trouble getting the stem to seal.

Not looking forward to reliving the tire mounting, or the unmounting before it... But mostly I want to make sure that the result is worth it. I want a valve stem that seals reliably.

These rims are fairly narrow; like I had to push the valve stem in and then pull it back down to get the beads settled, and that tells me everything's really tight. Could be that it's so tight the tire's distorting the stem's rubber cone... Anyhow, just hoping by now things have developed and there's a better valve stem.

Any thoughts?

I've not had any issues with valvestems sealing in the two tubeless conversions I've done. I have only used no-name bargain bin valvestems. I've had issues twice with rims leaking air around the tape at the seams of the rim, which was remedied by replacing the tubeless tape. 

How narrow a rim are we talking? It seems unlikely that the tires would be contacting the valve and deforming it. Does it inflate but then quickly deflate? Have you been able to seat the beads on the tire?

In reply to Erich :

TL;DR: Answers: Quite narrow but I don't have a measurement, agreed now that the beads are seated, yes it inflates and then deflates though we're up to 15 minutes or so, and yes the beads are seated.

I should also have at least started searching for valve stem options as long as I'm asking, which i haven't really. I'll probably ask at my favorite LBS while I'm grabbing more sealant.

I have never seated a tire as tight as this Schwalbe. I went into this going "gee, Jesse, your compressor isn't set up and you're going to feel a fool when you can't pump fast enough to get the beads blow onto the rim. Is this really a good time to be swapping tires?" Instead, the tire was so tight even sitting in the channel in the rim that it took air just fine and scooched the tire over onto the rim proper and popped into seating. I've seen no evidence of leakage between tire and rim, but it was obviously blowing air and bubbling sealant around the valve stem at the junction with the rim.

I've had a little trouble with this before, though not with these rims, IIRC. It really is narrow enough that I had to push in on the stem after backing off the threaded ring to push the rubber cone past the beads inside to be sure the tire wasn't sitting on the stem, which I'm pretty sure is what was going on even though it was blind by that time. When I got the first bead on, I had to remove the stem and then reinstall it because there was no way I was going to work the bead over the stem end. (I had started with the outside of the tire facing the rim, so when it first landed the stem was on the wrong side of the first bead or vice versa)

I don't have a great pattern for feel here because I've had a little trouble before, and never got the sort of succinct solution I would have expected from doing a sweep from "barely finger snug" to "I can't believe I'm using pliers on a valve stem ring, even if my fingers are slick with Stan's goo..." (and it was exactly that; I was a long way from cranking with the pliers, but in the spilling sealant I was unable to get any kind of grip with my fingers)

At this best this morning it was no longer dumping air, and took 15-20 minutes to go unrideable. I actually started heading for the trail at one point.

Anyhow, that's a really long story. All I really want to know is whether there's a better option than the default stems. These are decent quality rims (original equipment Stan's, so not top-shelf, and probably a notch down from their aftermarket bits, but a long way from junk), OE valve stems (now 3-4 years old)... It dawns on me that the prior stem trouble must've been on the prior bike, as I've never even removed these tires 'til now, just popped off a few inches of bead to add sealant a few times.

It does seem unlikely that the tires are pressing on the stem now that they're seated, but the rim really is so narrow that before seating fully there was zero extra room. It just feels like the rubber cone on the stem went straight from "not enough force to get a good seal" to "so much force I'm going to deform."

https://www.mtbr.com/threads/best-tubeless-valves-or-hacks-to-prevent-valves-from-leaking.1050377/

Now wondering whether I've damaged the rim tape while wrestling that insane tire and the air's just making its way from wherever I did that, through a spoke hole into the rim's box section and out around the valve stem... Guessing spoke nipples have enough tension to make them a better seal than just the threaded ring on the stem... How fantastic that I may have a couple of ounces of Stan's goo trapped in the box section...

TLDR - Cafe Latex (if they still exist) has/had nice tidy little valve stems

I've used Stan's valve stems with no issue.  I've also cut stems out of punctured tires and used them with no issues.  In fact, my tires currently have no sealant in them and have been maintaining pressure for a couple weeks (very little riding though).

The only thing I do that may be different is I double up the rim tape at the valve stem.  I start the tape just before the valve stem, do a full wrap, and cut it just past the valve stem.  Hopefully that makes sense.  I've been using clear gorilla tape for several years, and it has worked great for me.

I'm pretty sure I did just as I suggested in my previous post and damaged the old tape, blaming the valve stem because I didn't think about how box section rims are constructed (or about how likely I was to damage the rim tape). Which is pretty embarrassing after this long around bikes. Hey, I'm relatively new to swapping tubeless bits!

I've re-taped with Stan's tape (overlapping layers at the stem), fresh valve stem (the original WAS looking a bit chewed up from all my shenanigans), and there were no big leaks, and the small ones seem to be sealing after a couple rounds of reinflation.

I ended up just using whatever the LBS had on  hand for a fresh stem. I wanted to give in to my late-'80s/early-'90s mountain bike roots and get something aluminum and anodized, but they were on the long side...

The Schwalbe Nobby Nic was also much easier to deal with with some fresh Pedro's levers; I'd been using some old Bontragers that were excessively thick, compounding the tight-bead issue. I feel silly now that I also ordered some of the Schwalbe levers with the "hold the bead from creeping back off" clip since I couldn't find them locally and left the bike shop thinking I was going to have a repeat of the fight I had on the first mounting.