How to Refresh Sealant in Tubeless Tires

In the days leading up to a race, I get crazy about cleaning and servicing my bike.  In fact, my bike would rarely get cleaned or serviced if it wasn’t for an upcoming event. The old saying “the shoemaker’s children go shoeless” holds true to bike mechanics “care” of their own bikes. It really is shameful. Nonetheless, even if its only psychological, I think that a clean bike is faster, and a well serviced bike is undoubtedly better.  So I want to share one of my service tips that may seem a bit daunting at first, but is really pretty simple to do.

Tubeless tires have become the norm for mountain bikes.  The performance advantage of no flats, less weight, and more traction makes it a no brainer for anyone who’s looking to improve their riding.  Stans No-Tubes is the brand that really started the tubeless revolution as we know it today, and they are still the #1 choice in sealant for most riders.  Stan’s sealant does an excellent job of sealing most minor holes but does, however, evaporate over time so its important to check your sealant levels every 2-4 months.

There are a couple ways to tell if you need to add sealant.  One rule of thumb is to take your wheel off the bike, let it sit for 15 seconds and shake your wheel.  If you hear sloshing then your sealant levels are fine, if you don’t, then add sealant.  A more scientific way of doing this involves using an old bike spoke as a “dipstick”. With this method its critical to first set a benchmark dipstick level directly after a refresh or initial setup, so you have something to gauge against. With that in mind, and with the valve core removed and in the 6 o’clock position (see picture below), insert the spoke into the wheel to get a sealant reading, and refill as needed. Below are the steps necessary to refresh your sealant.

Step 1:  For this step you will need a Valve Core Removal Tool.  Hang the wheel so the tire is not sitting on the ground.  Position the valve stem in the 9 o’clock position and unscrew the valve core using the valve core removal tool, pictured in red below.  The tool will fit over the flats on the top of the valve, and will unthread the removable portion of the valve.                         

Step 2:  Thread on the Stans Sealant Injector Tool.

Step 3:  Remove the plunger from the syringe and fill the tool with the appropriate amount of sealant (for a 2? wide tire, 1-2 ounces for a refresh or 2-3 ounces for first time setup–wider tires will need more) making sure to kink the hose so sealant doesn’t go into the tire at this point.

Step 4:  Reinstall the plunger into the syringe and inject sealant.

Step 5:  Remove sealant injector, reinstall valve stem, and inflate tire.

Step 6:  Listen for air escaping, and roll/shake tire to move sealant to where any potential leaks may be. Some tires leak more than others and you may need to add air and repeat this step. It helps to spin the wheel while holding it parallel to the ground. This allows the sealant to coat the sidewalls of the tire.

Step 7:  Pat yourself on the back, crack open an ice-cold beer, and high five anyone around you.  You are now a master at refreshing tubeless sealant.

      So that’s it!  There’s nothing mystical or magical about tubeless tire maintenance.  Its a simple bike repair that you can do yourself with little know how and few tools.  Good luck and happy trails!