Why Is My Tubeless Tire Losing Air Pressure Overnight?

You suit up in your kit, grab a water bottle, and head outside to start your weekend off with a refreshing ride. But when you get to your bike, your tubeless tire is half-deflated, even though it was fine yesterday.

This guide breaks down why your tubeless tire is losing air overnight and how to pinpoint the exact source of the problem. Learn about sealant breakdown, valve leaks, rim tape failure, and more, plus the simple diagnostic checks and proven fixes you need to restore consistent air retention.

Some overnight air loss is normal. Losing a few psi overnight (up to 10% of the tire’s total air) may be normal, depending on the ambient temperature, age, and type of tire. More than 10% air loss may indicate poor tire construction, sealant issues, or a damaged rim.

A new tire or a well-maintained tire should not lose a significant amount of air overnight. If you’re having serious overnight air leakage, then sealant could be the cause. 

Ongoing sidewall weeping actively uses sealant to plug pores, leaving too little behind to maintain an airtight seal. Adding fresh sealant restores coverage and helps re-seal the casing. This is especially important during initial setup or after repeated air loss, as sealant can be used up faster than expected.

Generally, you should plan to replace the sealant every three to six months. SILCA's tubeless collection has the sealant, injector, tubeless valves, remover, and more that you need to fill and maintain tire pressure. 

Sealant issues often show up as:

• Dried clumps of sealant

• Uneven sealant coverage

• Sealant pooling inside the tire

These behaviors reduce the sealant’s ability to coat the casing and plug micro-leaks effectively. 

When sealant can’t properly spread or seal tiny pores, air escapes more easily. This leads to pressure loss even without a visible puncture.

A valve could be the cause of air leakage from your tubeless tire. It’s important to check the valve core, stem, and rim interface. 

A severely loose or damaged valve core is easy to spot, but a slightly damaged valve isn’t necessarily visible to the naked eye. It’s best to conduct a quick DIY test with soapy water:

1. Inflate the tire to riding pressure.

2. Mix a small amount of dish soap with water in a spray bottle or cup.

3. Spray or drip the solution directly onto the valve core and the base of the valve where it meets the rim.

4. Watch closely for bubbles.

Steady bubbling around the valve core usually indicates a faulty or clogged core. Bubbles forming at the valve base point to a poor seal between the valve and rim, often caused by overtightening, worn rubber, or damaged rim tape.

Worn rubber grommets or improper seating could also be the cause of your leak. You can try tightening the valve first. If this doesn’t make a difference, then it’s time for a replacement.

Air can leak from the valve base or spoke nipples if the rim tape is: 

• Damaged

• Improperly sized

• Incorrectly installed

• Aged

Signs of tape failure include bubbles, wrinkles, and sealant seepage. If you notice these issues, then it’s time to replace the tape. Try SILCA tape, with a triple-ply construction made of PET-PU composite with proprietary films for maximum durability and rim coverage.

It’s not usually a good idea to convert standard rims and tires that aren’t tubeless compatible into tubeless. This is a recipe for leaks and blowouts. 

Even with a compatible fit, some tires fit looser on certain rims, depending on the brand and model. Some tires may sit too loosely on a tubeless-ready rim, making it hard to seat the bead and causing air to leak around the rim bed. Difficulty pushing the bead out of the rim’s center channel toward the rim hooks can also cause air loss. 

Compared to road bikes, gravel bikes trend toward wider rims and wider tires, which can shift fit in a way you’re not used to. Not sure how to get a good seal on your tire? Follow these tips:

• Use soapy water on the bead to help it slip into place during inflation.

• Apply fresh rim tape to increase the internal rim diameter and help snug the bead.

• Use a quick burst of higher pressure to pop the bead onto the rim, fully sealing it.

If your sidewall or bead is faulty or misshapen, air could leak out of your tire. Inspect the bead and sidewall carefully for possible leaks. 

Improper bead seating may result in continuous air loss until the bead is straightened and reseated. A kinked tubeless bead allows air to escape under the bead, preventing the tire from sealing properly.

Dust or debris and deformations from installation tools can also prevent an airtight seal.

Yes, porous casings lose air faster, especially on supple gravel tires. Some lightweight tires may break in after a few rides due to the rubber settling. You may need to double-check the sidewall after your first few rides. 

Temperature-related pressure changes can make your tire deflate or expand, potentially causing leakage. This phenomenon is common in the variable temperatures of summer and winter. Try to store your bike overnight in a more temperature-controlled environment, if possible. 

For gravel bikers, rough terrain also impacts bead stability. The right equipment for your terrain, and tire pressure testing before a race, can significantly improve tire integrity.

Use these methods to maintain proper air in your tires overnight.

Make the following adjustments to prevent more leakage:

• Add sealant/balance sealant distribution.

• Tighten the valve core, clean, and reseat the valve.

• Inspect and reseat the bead.

• Inflate with a high-pressure floor pump.

When you come back the next day, the pressure may still be a little low, but this should solve your sidewall weeping issues. If your tires are still losing air every night, check out our tubeless tire troubleshooting guide.

If your tires are continually leaking air, you might need to do a full re-setup. Here’s how: 

1. Remove the tire and inspect the tape thoroughly.

2. Re-tape the rim with quality tubeless tape.

3. Reinstall the tires and perform a firm bead reseat.

4. Shake or rotate wheels to coat the interior casing with sealant.

It’s time to start replacing tire components if you notice:

• The casing is too porous or worn.

• The valve stem is deteriorating.

• The tape is continually failing.

When weighing the benefits and drawbacks of tubeless tires, you need to know how to keep your tires in good shape.

Check your tire pressure before every ride, always store your bike in a temperature-controlled space, and get on a regular sealant refresh schedule.

If you’re a gravel or adventure rider, plan to check and maintain your bike at least once a week. SILCA provides high-quality pumps and pressure-accurate tools for proper maintenance to help you keep your tubeless tires in great shape.

A tubeless tire losing air overnight is usually fixable with fresh sealant and proper maintenance. 

Equip your setup with SILCA’s precision pumps, sealants, valves, and tubeless tools to prevent overnight air loss and ride with confidence.

Yes, small pressure drops are normal, but rapid loss signals an issue. It indicates a problem, such as a poor bead seal, dried sealant, or a valve issue.

Yes, brand-new tubeless tires often lose air more quickly at first. The tire casing can be slightly porous when new, allowing air to escape until the sealant fully coats and seals the internal surface.

Yes, insufficient or dried sealant allows micro-leaks to remain unsealed. About once a year, we suggest removing the tire and cleaning out the dried sealant, so you aren’t carrying extra weight in the tire.