Tubeless tires, low psi - how does it hold air?

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wheelsONfire
Posts: 6280
Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

You guys who run tubeless, how good does it hold air/ pressure?

Since most run so low psi in wider tires, it seems a big chance pressure gets really low while riding?

Came to think of this as i've seen some latex tubes dropping pressure really quick.
No tubes in tubeless ofcourse, so i don't really know what to expect!?

On my road bike i run about 100-108psi front, 108-118 psi rear.
What would i ride on a gravel bike with tubeless tires (30-36mm tires)?

I am 77Kg's without the "cycling uniform" so perhaps i am a bit over 80Kg's with bottles and shoes :-)
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

mattr
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Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

Gravel bike, so not racing CX?

You'd probably be looking at 40-45psi, and at that pressure even a badly sealed stans tubeless (with non-tubeless tyres and bugger all sealant) would probably take 24 hours to get too soft to ride. My wife runs 20-30 psi for cross (Stans conversion) and it takes a couple of days to soften noticeably.

With a tubeless ready tyre and/or a decent amount of sealant, you might be looking at a week or more.

And FWIW, they run fat bikes with tubeless at <10 psi with no major issues.

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rrkite99
Posts: 12
Joined: Wed Oct 19, 2011 5:06 pm

by rrkite99

Road tubeless: In 24 hours air loss I pump them up two to 3 pumps the next morning. Some tires will flat after several weeks. It seems the more you spin the sealant the better it works. My low pressure fattie tires I only pump every couple of days. This makes it seem the higher the pressure the more leakage so gravel tires should last quite a while before needing top off.
I might be biased but if I never saw another bike tube it would be fine with me.

Marin
Posts: 4035
Joined: Wed Jan 22, 2014 11:48 am
Location: Vienna Austria

by Marin

On my MTBs with 55-60mm tires I run tubeless 1.2 to 1.4 bar (17-20 psi) and they hold the pressure for weeks. On the CX with 37mm tires, I can also go for a week without needing to top up.

Generally, a properly sealed tubeless rim & tire will hold air as good as a butyl tube.

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wheelsONfire
Posts: 6280
Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

Thanks guys!

Nope no CX racing. Been waiting too long for my bike and all sorts of questions pop up at times.
But this is great to know. No need to worry now :-D
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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