Jim’s Tech Talk
By Jim Langley
Everyone loves a good bike tip and I have one for you today from regular contributor to RoadBikeRider, Seth Shaw who cycles on the sometimes-rough desert roads of Arizona where tubeless tires help smooth the ride. He has a simple tip and one that solves a common problem with tubeless tires: valves clogged with sealant.
What happens over time is that the sealant inside can clog at the base of or inside the valve. When this happens it can become difficult – sometimes very difficult – to let air out of a tubeless tire or pump it into the tire to top it off too.
The first step to fixing this problem is removing the valve core. The easy way to do this is with a valve core tool, such as Park Tool’s VC-1 Valve Core Tool https://amzn.to/4djBLam It can also be done with a small adjustable wrench or even a pair of pliers, but be sure to work carefully or you can damage the valve and/or valve core.
Removing the valve core will let the air out of the tire. If it’s clogged, the air will come out but, depending on how badly it’s clogged, it could happen very slowly.
The next step is to clear the valve of the clog. This is where Seth’s tip comes in. I clear clogs with anything I have handy to poke inside the valve and break through the clog. For example, the threaded end of a spoke works well. Note that if you use something pointy, be sure not to push it all the way inside the tire until it touches the tire as you could puncture the tire.
I bet even a spoke could puncture a tire if you pushed hard enough. So I think Seth’s tip is a superior solution.
He says, “I discovered a better way to clear valves of clogs by using pipe cleaners. They have to be sturdy with small built-in prongs, not like those ones your father used for pipe cleaning. Here’s a link to the ones I use. They are the perfect diameter for Presta valves with hard bristles to scrub valves clean: https://amzn.to/4kbcp1b. They’re much better than anything I’ve previously used.”
Thanks for the great tip Seth! Readers, if you have a helpful bike tip you’d like to share, please send it in to me at [email protected] and I’ll consider using it in an upcoming Jim’s Tech Talk.
Jim Langley is RBR’s Technical Editor. A pro mechanic & cycling writer for more than 40 years, he’s the author of Your Home Bicycle Workshop in the RBR eBookstore. Tune in to Jim’s popular YouTube channel for wheel building & bike repair how-to’s. Jim’s also known for his cycling streak that ended in February 2022 with a total of 10,269 consecutive daily rides (28 years, 1 month and 11 days of never missing a ride). Click to read Jim’s full bio.
I store my bikes with the valve stem between 5 and 7 o’clock so sealant doesn’t pool in the valve stem. I’ve never had clogged valve stems.
That’s an interesting approach syborg. The sealant should run to the bottom of the tire. Since the valve is on the rim not the tire the sealant shouldn’t be pooling on the valve no matter where you place it right?
Jim
They’re definitely more expensive, but Santa Cruz Fillmore valves have never clogged on me. They make filling a tubeless setup easy.
Most carry a multi-tool. What size Allen key would work to clear a logged valve?
A 3mm should work Richard so long as it’s long enough to reach the bottom to break through the clog.
Hope this helps,
Jim
Or give up tubeless altogether. I was never convinced this was the be all end all as it’s marketed by the bike industry. I have moved back to tubes and with TPA I get light weight 32 to 38 grams, extreme puncture resistance, and can run them all day at 65 to 70 psi on my road and off pave bikes riding 32 to 45 mil tires. Are they perfect, of course not but in a year and a half nary a pinch flat or blowout
TLR tires are heavy, expensive, hell to mount, and sealant snot is the bane of existence. A classic case of solutions looking for a problem like hookless rims and disk brakes.
I use the same type of pipe cleaner, but I dip the end in alcohol. The alcohol seems to soften the clog.
I do too, Paul. Works well.
Beat me to it! I’ll ride tubeless when I get sponsored by a team and the mechanic swaps out my wheel when I puncture.
I use WD40 squirted into the valve core as it (slowly) disolves the sealant and prevents buildup.
Place a drop of oil/wet lube down the valve stem and place another drop on the bottom half of the valve core., prior to inserting and tightening the valve core. NO MORE CLOGGED VALVES! I’ve been doing this for 5 years now; solves the problem and there’s also nil impact on your tubeless sealant.
Another method mentioned by the folks at Silva. Use a Q-tip lightly coated with oil and, with the valve core out, run it through the valve barrel twirling it as you go. It’s worked well for me. Not completely foolproof, but does help a lot.
Thank you However, I use the Reserve Wheels Fillmore Valves for more effective air flow while mounting. ( they work well). The core is not removable from the outside ( although I took them apart on the table top). I still suffer from clogged valves and have been using Orange Seal Endurance……that stuff really works well !…so well it can glue the tire to the rim making it impossible to remove. I recently went back to Stans since it seems to be lighter and remains in a liquid state longer (now I have been experiencing air loss again). Anyway, I was thinking of injecting some K2 in the valve stem often to dissolve any sealant residue and help keep them clear.
I use a pipe cleaner with a bit of oil-based chain lube. The lube helps to keep the sealant from sticking in the valve.