Having a consistent leak on my tubless gravel tires. It’s coming from the base of the valve stem where it meets the rim. I tightened it but it did not solve it. Any tips, or do I need to replace the valve stem? The valve stem core is brand new, so I don’t think that’s the issue.
by sk8klown88
4 Comments
Make sure the valve is seating properly in the rim, no dried sealant, fully inserted.
Make sure your rim tape is flat and adhered to rim bed.
Make sure you have enough sealant — it shouldn’t *keep* leaking, that’s kinda the point of tubeless.
If the valve nut has a recess for an o-ring it needs an o-ring, or you need a different nut.
I had the same problem this fall. I assumed it was bad/old/moved around rim tape. So I took it all apart, scrubbed the rim clean, put down a fresh strip of 1″ gorilla tape, pressed nice and firm. I reassembled everything, mounted the tire, and still the valve leaks. No matter how tight i crank the collar. Its as if theres a crack in the metal somewhere letting the air through, but everything looks perfect. And its a Reserve stem for me, so I don’t think its even possible for them to leak air into the hollow part of the rim, unless the rubber itself was bad. But that also looks totally fine. It is a mystery. Next season I’m drilling out the rims and installing schrader valves.
Sometimes the valve itself sort of has the wrong shape for certain rims. There are valves with different shapes at the top, the part that sits on the rims. Some are more rounded, some are flat. Maybe try a different type of valve maybe?
It’s quite possible that the tape has failed somewhere else on the rim, and the resulting air in the rim chamber is just escaping at the valve, because there’s not an airtight seal on the outside of the rim/valve intersection like there is on the inside.
TLDR: it’s the tape, but not necessarily at the valve.