I’m currently running Maxxis XC Extremes with DT Swiss conversion kit on Mavic 717XC rims at 35 psi.

How low do you go without burping?

nowhere near as low as with a dual ply DH tyre and a nice thick inner tube.

I never go below 35 with any of my UST’s, because they start to squirm around in a disconcerting fashion. 30psi is generally the minimum recommended, IIRC, and I wouldn’t go lower than that. With the narrower 2.2 CXR’s I use about 37/38, and the bigger 2.3 ACX’s 35. Of course, this is a purely personal thing, and trial and error may tell you more! ;0)

27 psi is the min for me, 25 is too low.

(on the front on rigids) back will be a couple of psi higher

Lowest has been 25psi but that was on a horrible slippy climb when anything higher just wouldn’ give traction. I wouldn’t run that low again unless I ran into the same conditions.

I run 25psi in a front High-Roller & 30-35 in the rear

I went tubeless and was a little disappointed as i couldn’t go as low as i had been using – 19psi on a 29r 2.4 stout

have to run about 30 now

The tyre pressure you run will be a factor of
1. Your weight
2. Tyre width
3. Rim width
4. Tyre/rim combo (some tyres are tighter than others).
5. How hard out you ride. If you never push your tyres very hard then they are never going to burp.

Without all of the above info your “what pressure” question does not tell us much…

I run 27 psi in my 2.35 Specialized Eskar 2Bliss controls mounted on DT 5.1 rims with the DT tubeless conversion kit. I only weigh about 70kg (11 stone) and push my tyres pretty hard on my 5-Spot.

Oh, and I have found you can go a lot lower in pressure with real UST tyres and UST rims. Conversion kits and non-UST tyres run with goo are much easier to burp!!

Depends more on your BMI …The higher your BMI the more PSI 😀

~20-22psi with UST RR’s on Stans rims, 70kg on Turner Flux. Tried 18psi, but that was too squirmy.
IMO over 30psi is WAY too high, regardless of your weight/style/blah blah.

I used to run Tioga FAT 66 DH 2.1 tyres at 15psi when I was experimenting with DIY tubeless. They gripped very nicely, but for a while I became known as the man with the farting bike 😀

I run a more normal 30 psi on my ust’s.