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As per the title.
Been up to Comrie today and despite having a blast in general I had to knock it on the head early after a couple of VERY sketchy moments on the blue berms. Realised I'd rolled the tyre off the rim enough to lose almost all air pressure, even though (as far as I can tell) I was riding centred on the bike so not putting any lateral pressure on the wheels.
Am I just running the pressure too low? It was about 45 psi. Tbh it's been that long since I've ridden in anger that I've forgotten, apart from borrowing a mate's Trek Stache which has very low pressure monster truck tires.
You should not be burping at 45psi, I'd question whether the bead was correctly seated.
Tubeless setups for MTB should be far lower than 45psi without burping being an issue.
What tyre / rim combo?
It's a Blue Flow rim with Magic Mary
45psi is crazy high.
45 psi suggests your pump gauge is wrong. But a standalone digital one and measure with that.
Hmmmmm, could be. The pump is a fairly old eBay special. Very likely the gauge is off, although the tire felt "ok" with a squeeze test before I set off. Will give it a look. Cheers.
Could you have lost air due to a puncture which sealed up, and then rolled the tyre as a result?
I tired to get 45 PSI out of this, needed a 150 BG Pro DH rider on XC tyres but I got there
https://www.schwalbe.com/en/pressureprof
Why would you have 45psi in your tubeless tyres? Some of them setup tubeless aren’t even rated to run that high anpressure I don’t think.
The most I run is 25 psi on stuff where it’s rocky and I’ll be hitting stuff harder - otherwise it’s 23psi front and rear most of the time. I go down to 18pai front / 20psi rear if it’s slow speed / steep / super sloppy mud.
I’m about 75-76kgs though - so not the heaviest. Appreciate if you’re heavier you may need to run more - but wouldn’t think 45psi.
Are your rims and tyres definitely rated for running tubeless?
I'm wondering now if it was so tight that it caused the burp. No idea, but the tyre says max 50psi. I just stuck the track pump on it to check before I went off to Comrie. Either way, I've reinflated to a more sensible 25psi and all seems to be ok, although being a bit of a lardy it does feel slightly flat for my liking.
As for if they're rated for tubeless, the rims definitely are, the tyres I've never had a problem with Magic Mary for the past couple of years they were on my Banshee.
45psi would feel rock hard if the tyre is wider than 2.3. Sounds like a dodgy gauge.
I think 45 psi is getting towards the upper limit for a tubeless mtb tyre. For a wide tyre on a wide rim it could be over the safe maximum
The most I run is 25 psi on stuff where it’s rocky and I’ll be hitting stuff harder – otherwise it’s 23psi front and rear most of the time. I go down to 18pai front / 20psi rear if it’s slow speed / steep / super sloppy mud.
I am c85kg and running the same. I did a ride last week, Dad's n kids at Swinley and the pressure was too high at about 30, possible less. It was a miserable ride but couldn't be bothered to stop and change it