Pinch for Seal
Mountain bike tubeless tires work much the same way as car tires. By having a pronounced inner-sidewall to correspond with the dedicated rim, tubeless tires form an airtight seal when inflated. Due to this airtight seal and no inner tube, tubeless tires are not susceptible to pinch flats.
It is possible to retro-fit older inner tube based rims. This works by using edged rims that can support the airtight seal when the tubeless tire is inflated.
One of the benefits of how tubeless tires work is reduced weight and "rolling weight." A tubeless tire has no need for the extra weight from an inner tube, thereby reducing actual and rolling weight.
Many mountain bikers like being able to run tubeless tires at a lower PSI (pressure per square inch) than traditional tires. Tubeless tires can be run this way as a result of the airtight seal and pinch flat-resistant tubeless system.
A tubeless tire presents more work during installation and when fixing or changing a flat. Because the seal must be precise, the user needs patience and special tools to mount and inflate the tire in case of flats.
Article Written By Eric Cedric
A former Alaskan of 20 years, Eric Cedric now resides in California. He's published in "Outside" and "Backpacker" and has written a book on life in small-town Alaska, "North by Southeast." Cedric was a professional mountain guide and backcountry expedition leader for 18 years. He worked in Russia, Iceland, Greece, Turkey and Belize. Cedric attended Syracuse University and is a private pilot.