I have a couple of bikes running tubeless setups and I’ve noticed an odd issue. When I try to top up the tyre pressure using a portable inflator, the inflator cuts out early, leaving the tyre several PSI below the target pressure. To work around it, I have to set the inflator higher than the pressure I actually want. I also struggle to get accurate pressure readings using a separate tyre pressure gauge.
What’s strange is that if I completely deflate the tyre, remove the valve core to inspect it (it’s clean and not clogged with sealant), reinstall it, and then inflate the tyre again, it reaches the correct pressure without any issue using the exact same setting.
On a bike running standard inner tubes, the pump works perfectly fine, so it seems to be something specifically related to the tubeless setup.
Any feedback or suggestions would be appreciated.
partially blocked valve leading to high pressures to get air in?
BITD the little nut-thingy on the top of a Presta valve could be unscrewed too far for some push-on pumps to inflate (looking at you, Campagnolo Art. 1030 / 2).
Try unscrewing it enough that it allows air in/out, but no further
One of my electric inflators has started doing this, it must be a valve issue
Clean the actual valve body, not just the removed core
The valve core is clogged with sealant, just not on the ends you can see.
