A tubeless valve stem is a tubeless valve stem, right? Not so fast. When it comes to tubeless valves, Nex-Gen Sports claims that all are not created equal. Rather than being constructed from “thin wall, welded or extruded aluminum tubing,” Nex-Gen Stem Gems are machined from solid bar stock which is just the start…
Starting with cold drawn solid bar stock, Stem Gems are CNC machined and then put through a “multi-stage anti-corrosion process that exceeds both American STM B117 and ISO/DIS 11130/2017 international standards.” Seemingly through their own testing, Nex-Gen claims that their valves are up to 200% stronger when compared with five other brands of extruded valves with similar lengths and identical wall thickness.
To make the sealing components more durable, all of the rubber pieces are removable and replaceable. The ends also feature a 4mm Allen fitting to help tighten them to the rim when first fitting them. Nex-Gen claims the alloy head of the valve stem is specifically engineered to work with their tire sealants without “causing ‘balling’ of the sealant ingredients.”
Offered in 42, 62, and 95mm valve lengths, actual weights start out at 4.7g for the 42mm valve with the cap. Sold as a pair in all black with a clear cap, the Stem Gems sell for $19.99.