MM/HD tubeless pressure advise

Just fitted. Bronson CC on flow EX’s rider around 14stone with backpack ready to rumble. What pressures should I be running? I’m riding the Peak District and some trail centres ect. Thanks.

I normally run 15 front and rear for general trail riding on my nomad but increase to 20 at the back if I’m jumping or on a dh track otherwise the tyre squirms a bit too much. I have accidentally run the front at 7 and the rear at 9 which offered amazing grip but I could feel the rim hitting stuff.
My rims are light bicycle 30mm internal and 650b.
Which version of the tyres are they as that makes a huge difference?

There’s a formula for a starting point as far as tubeless pressures go. It is a stating point though, as many factors including terrain, riding style and the all important subjectivity of how each rider likes their bike to feel.

Formula is something like: Rider weight ( including kit etc) in pounds ( in your case, 14 stone x 14 = 196lbs) divided by 7 will give you the pressure in psi. Then add a couple of psi for the rear and deduct a couple of psi for the front.

So maybe you could start with 30psi at the back and 25 psi front.

Give it a go and see how you get on. There are no absolutes, it’s all down to you!

Cheers guys. Much appreciated.

14st. 29er rider here.35mm light bike rims.

Mostly natural trail riding with the odd trail centre. 18psi front, 20 rear.

Mostly that works fine, and I can go down to about 15, but the incidence of rim strikes starts to go up then, especially on the back.

For things like Snowdon and the lakes, I’ll run a few Psi higher.

Generally I’d like to run lower pressure, but I’ll need to swap out to either some super gravitys, maxxis double down or similar for that, and at the moment, for a trail bike, I’m not sure I want to pack the additional weight.

Twice your weight in stone in psi is a good starting point. Go up if it squirms or pinch flats, down if it boings or skitters about. Bigger tyres (both width and diameter), wider rims and heavier casings allow lower pressure, and vice versa.

Bike pressure gauges can be really inaccurate at tubeless MTB psi, it’s so much lower than road bike pressures, so don’t trust the gauge (or other people’s recommendation) unless you’ve got a few gauges to check accuracy – ride feel (not thumb test feel) is the best indicator if your pressures are right or not.

I’m another 14st rider using MM/HD on rocky Lakes stuff etc.
40mm rims on Liteville 601. Tubeless with Tape/Stans.

Front is a 2.5″ vertstar snakeskin MM (a special for LV, not generally available)
I can get away with about 20-25psi.

Rear is 2.3″ trailstar supergravity HD. I can just about manage to get down to 30 psi but at that I’m feeling the rim strike a little too often and am more comfortable with 35psi.

I’m waiting impatiently for Procore, so that I can drop pressures at both ends.

Am 13 stone without kit. Run MM / HD combo

Usually run 24 front, 27 rear