The rim’s inner channel is the lowest point, which will give you the most tire to work with on the other side, so it often helps to place the first side of the tire that you mount into the rim channel. Next, be sure the tire bead isn’t caught on the tubeless valve. If it is, push the bead of the tire over the valve to cover it. From there, we recommend starting at the side of the tire opposite the valve and working your way around, pushing the bead over the rim. Of course, you can use tire levers, but be careful not to poke a hole in the tape.
• Tape choice and valve installation are crucial: Tubeless tapes come in a variety of widths to cling to the rim and keep the spoke holes from leaking air. Make sure to figure out the correct tape needed to match the inner rim width of your wheelset. Some riders recommend Gorilla tape; however, tubeless-specific tape is the way to go because of its tackiness and slimmer profile. It’s important to clean the rim completely to help make the installation of the tape easier. Once the tape is properly installed, you must poke a small hole in the tape for the valve to poke through. We typically use an old, sharpened spoke to start the hole and then slowly push the tubeless valve through the tape, being careful not to split the tape.
From here, we take a simple step to maximize the rubber seal on the tubeless valve by butting it up against the rim and tape. To completely set the valve, make sure to tighten the valve collar. It’s important not to over-tighten the collar, since doing so will make it nearly impossible to put in a tube—should you need one later down the road.
• Soap and air compressors rule: Tired of trying to use a floor pump? Tubeless tires need a quick rush of air for the tire to seat onto the rim. Yes, there are tubeless pumps designed to manually pump and compress air into a chamber, but if you have a compressor you can save yourself some time and energy. If needed, you can remove the valve core to allow maximum airflow into the tire. Now, let’s say you got air into the tire but the bead won’t quite seat. What now? To problem solve, we let some air out and then spray or rub soapy water around the bead to help it snap into place once air is added again.
• Inserts and mixing: While tubeless tires don’t get pinch flats, they can sometimes burp out air. That usually happens when a wheel hits a bump sideways, bending the tire to one side and opening a gap between the tire and rim, releasing air. In the best-case scenario, this only lets out a bit of air. At worst, the tire can come off the rim. If the tire does peel off during a downhill run, in an enduro race or on a harsh trail-riding day, it could do some serious damage to you and your wheels. One option is foam-based inserts (such as Cush Core) that are designed to go in a tubeless tire system. The foam inserts do add weight, but they also offer sidewall support with lower tire pressures while protecting the rims.
Should I Run Tubeless?
Tubeless systems seem to get better every year, and there’s no doubt these systems work well. Currently, we think the benefits of running a complete tubeless setup outweigh the cost; however, if you only enjoy an occasional bike ride, a tubeless system might not be worth it. Keep in mind the fact that a tubeless system needs more maintenance than an old-fashioned inner tube. That said, any true mountain bike enthusiast will likely find a tubeless setup is a more-than-worthy upgrade for a modern mountain bike.
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