Tubeless sealant and valve stem

orraloon

Numpty question from 1st season user of tubeless setup.

Is it better to store bike wheels with valves in the 12 o'clock position?

Cleaned out valve stem 2 weeks ago, waggling a sharp stick inside to clean out the gap. Was blocked so could not inflate. Tyre had liquid sealant inside, evidenced by small seepage around rim when deflated. Topped up anyway as valve core was out.

This morning find the valve is blocked up again. Had not ridden this bike for a week.

So would it help if I remembered to leave the bike with the valves at the top?

orlok

orraloon wrote:

Numpty question from 1st season user of tubeless setup.

Is it better to store bike wheels with valves in the 12 o'clock position?

Cleaned out valve stem 2 weeks ago, waggling a sharp stick inside to clean out the gap. Was blocked so could not inflate. Tyre had liquid sealant inside, evidenced by small seepage around rim when deflated. Topped up anyway as valve core was out.

This morning find the valve is blocked up again. Had not ridden this bike for a week.

So would it help if I remembered to leave the bike with the valves at the top?

I believe it's the best thing to do, store the wheel with the valve at 12 o'clock position, at least I do it too.!

cycleclinic

What sealant, Stans race perhaps. They say that blocks valves and Stans does not lie, it does.

Nick Payne

I use orange seal and I store wheels/park bikes with the valves at six o'clock. The valves don't clog up - I've had the same valve cores in there for a long time, removing the cores every few months for either additional sealant or when tyre needs replacing, and the cores are still fine.

orraloon

thecycleclinic wrote:

What sealant, Stans race perhaps. They say that blocks valves and Stans does not lie, it does.

Hi Malcolm. It's yours! The Effetto caffelatex sealant. The blockage is forming where the valve base bit (whatever is the right name for that) goes through rim, not in the valve stem tube itself. The valve itself is clean. Oh and seems, so far... to be the front wheel only.

Will try leaving wheels valve-up, see if makes difference.

StillGoing

Surely you'd store with the valve at anything from 4-8 o'clock so that fluid drains out of the valve stem. With it at 12 o'clock, it'll just settle in the stem.

zefs

I don't think the sealant will clog the valve at 12 o'clock, which is the recommendation. The sealant doesn't have the height within the wheel to overpass the valve and clog it. Some sealant will get on the valve with road bumps (my guess) which is normal. On my setup the nut sometimes become stuck and doesn't unscrew but if you wiggle it it gets unstuck easily.

Because you use Caffelatex, which works a bit different it's recommended by the company to not mix it with other sealants and to not inflate with the valve at 6 o'clock with a compressor which can dry it out.

Which valves are you using? Maybe too much sealant?

The Rookie

Maybe the valve is leaking slightly and the escaping air is carrying the sealant into it. I had that once, the removable core wasn't quite sealing.

It shouldn't set if its in the wheel and tyre so valve location shouldn't matter, but as above at 12 o clock it can't drain any sealant out but will sit on the back of the core ripe for blocking it, while at 6 o'clock it should be well clear of the sealant, so any position BUT 12 o'clock sounds better!

orraloon

Thanks for the inputs. No mixing of different sealants. No CO2s or the like. Might be excess sealant.

Valve core and stem tube seem clean. If valve was leaking, would expect sealant traces present on the valve core. Seems like a skin is forming across the base. Remove valve, tyre stays inflated. Press a sharp stick, cocktail stick style, in, get slight hiss, remove, hiss stops. Using a blunt end metal drill bit, blunt end in first, of correct diameter, appears to dislodge / break the blockage, tyre deflates. Pump it back up.

What I should do is remove tyre, clean it all out, and start again. Sort of goes against the model of tubeless tyre never comes off until time to replace, but hey ho. In meantime I'll see if parking up / down / sideways makes any difference.

The Rookie

Must be more than a thin skin if a track pumps circa150psi (less existing tyre pressure) can't blow through it!
I wonder if there is a 'blob' in there attached at the valve and when you open the valve the airflow moves it into the stem so it plugs it. All you do is push it clear and then it comes back in again.

zefs

Forgot to mention, you must not overtighten the ring that touches the rim because the more you tighten it it pulls the plastic from the valve and can damage it which can then cause a leak.