First the caveats, this is about a tubeless sealing problem, second, I have been messing around with tubeless set ups since 2004/5 when I imported a load of Stans sealant, theoretically I should have the answers to any tubeless problem but I don’t.
I have a brand new set of Hunts Trail Wide wheels, tyres are brand new Maxxis Minnion DHR 2s, with foam inserts and a good dose of Stan’s.

Here’s the issue, the front wheel leaks at a fastish rate through one spoke, every other area is tightly sealed. The rear wheel leaks through several spoke holes at a slow rate (ie goes flat over night)

In the case of the rear wheel after the first leaks I reinforced the the original Hunts rim tape with three wraps of heavy duty cling film (ghetto tubeless that I have successfully used to convert my fat bike to tubeless) and whilst this reduced the rate of leakage it hasn’t stopped it.

I am struggling to understand why air can come out of spoke but the sealant not reach it to seal it as it did with minor side wall leaks, also if the there is air at a spoke hole then that says the rim tape is compromised so then why then is air not flowing out of multiple spokes ?

If you have ideas please shout up because the Minnions with the foam inserts are very very difficult to remove/fit and I am becoming a tad peeded off by the continued leaks.

PS please “no put some tubes in it and stop the faffing”, I have been riding tubeless for 17 years and have no interest in going back to tubes, thanks Paul B

What tape did you tape the rims with?
Sounds like a poor taping issue to me.

I’ve done countless wheels with two wraps of Tesa tape and never had any issues.

All my MTBs have sealed with gorilla tape.

My gravel wheels front rear has been fine with gorilla tape but the front would only seal with tessla tape.

I’d try a different tape type.

I’d try a different tape type.

Tesa/Tubeless tape imho is not the easiest to apply flat.
You have to clean the rim meticulously with alcohol and have the wheel in a position where you can put some decent tension on the tape as you apply, smoothing it completely flat and removing any air bubbles as you go.
It crinkles very easily so leaks are likely if you’re not meticulous.

Be meticulous.

Thanks for the Tesa tape recommendation, my roll should arrive tomorrow.

Having removed the Hunts rim tape I think I now have an understanding of the problem.The tape has an adhesive backing which appears to work well enough to isolate any leakage to its immediate vicinity. What appears to have happened is the sudden influx of Co2 has forced the somewhat rigid Hunts tape hard against the spoke aperture and in doing so has caused the tape to tear/shear against the sharp aperture edges.

In the case of the spoke that was leaking at a fast rate the pressure has cut a hole through the rim tape in the exact shape and size of the spoke aperture. I find this surprising but the evidence is crystal clear so I am going to give the Tesa tape a go and see if there’s a softer way to inflate the tyres.

Thanks for the Tesa tape recommendation, my roll should arrive tomorrow

Tesa is the brandname (in case you weren’t aware) and they do loads of tapes.

It’s Tesa 4289 You want.
The yellow stuff.

I wouldn’t have thought your inflation method would cause a problem. I inflate mine with an air compressor. Many inflate theirs with one of those pumps that release a big blast of air at once.
Shouldn’t be an issue.
It’s what you do.

Sounds like maybe your Hunt tape wasn’t applied well maybe.

It’s also possible that the CO2, being so cold on release, has hardened the original tape, making it more brittle and hence more likely to tear?

My method has always been to use tape that is wider than the internal rim width. That way, the seal is always bead-to-tape and, other than where the tape crosses over itself, nowhere for air to get under the tape. I know this can it more tricky to change tyres without damaging the tape, but I only change them when they’re worn so not an issue for me.