Lubricated valve stems

10/09/25 19:49 Filed in: Gear

Another great idea from Josh at Silca. To prevent the sealant from sealing the valves on your wheels, lubricate them! Sealant and lubricants do not go together well. Josh recommends a lube with adhering microparticles (molybdenum disulphides, as an example - I think the Silca Synergetic has tungsten-based particles).
I didn’t have any of those, but I do have a quite full bottle of Shimano dry lube with PTFE (teflon) particles. I gathered all the good valve cores I could find in the house (16 of them) and put them in a small cup. I poured in a few millilitres of Shimano dry lube and left them to sit. I got a chance to use one on Monday. The valve stem in my commuting bike had a sealing incident. That was last week and it has been extremely difficult to pump up the tyre since. The pump needs around 100 psi more than the tyre to force the air in. Lots of pumping for not much result.
The lubricated valve core works really well. The locking knob on the tip turns smoothly with some lube on the threads. The plunger portion moves up and down easily lubricated.
I think this is going to pay off.
As I swap in the lubricated cores for the ones in use now, I can drop them in the dry lube to bring them up to speed. Which is good because there are more than 16 tubeless wheels in this household.
The other task Josh suggested was running a lubricated pipe cleaner up through the centre of the valve stems to prevent sealant from sticking to them as well. All of my MTB wheels have CushCore in the rim, necessitating valve stems with a 90 degree bend in the air passage (if it ran straight through like a “regular” valve stem, it would get blocked by the insert). They can’t be run through with a pipe cleaner (or anything else) but maybe a cotton bud with oil on it? I’ll have to see what I can come up with.
I think the cores are the more important part of this equation.

Michael Hanslip Coaching

If you want to go faster, you have to pedal harder

Lubricated valve stems