Bead Socket Technology rims are designed to match the shape of your tire's bead to create a safer and more secure air tight interface. Unlike the secure “socket” of a BST design, conventional rim shapes drive the bead of the tire down deeper into the rim, putting pressure on sidewalls that causes friction, restricts tire volume, and keeps the interface from forming a sufficient seal for tubeless use. BST rims secure the bead of the tire, not the sidewall, creating an air tight seal while allowing the tire's sidewall to expand to its true, rounder, more effective profile. The result is more traction and less rolling resistance. With lower-profile, less vulnerable sidewalls, our BST rims are also lighter and stronger by design, and accelerate more quickly.

Our BST system was developed specifically for tubeless use with pressures below 45psi. From our Iron Cross to our Hugo, we offer low pressure BST rims for tires in the 32mm to 122mm width range. The broader pressure range of our BST-R Series rims and wheelsets means they're optimized for tubeless use with tires in the 32mm to 50mm range at pressures of 45psi or lower, as well as 25mm to 32mm tires specifically designated as "tubeless" that feature reinforced beads designed for pressures up to 115psi. Both BST and BST-R rims and wheelsets may be used with tubes.

We all know the most important piece to the bicycle-terrain interaction is the contact patch between the tire and terrain, so tire profile and tire pressure play huge roles in bicycle performance and overall handling. But many rims just don't work well with the tires we're all using. Rims that are too narrow fail to offer sufficient sidewall support and protection to your tires and create a less stable shape. The result is less control in the corners, less traction on climbs, and more rolling resistance. Rims that are too wide also distort the tire profile, decreasing traction and control and driving impacts directly into the rim, negating the impact absorbing advantages of a tire's volume. Our WideRight rim widths are designed to strike the perfect balance between tire volume and sidewall function.

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