The new 500g single wall fat bike rim from LB
After years of development, Light Bicycle is excited to announce our first single wall fatbike rim! Weighing in at just 500g, you’ll drop a significant amount of rotational weight from your fatbike without compromising strength or stiffness.
The FS680 is a 26” rim and features an 80mm internal width.
Example Wheelset Build: ONLY 1700G!
Hub: Tune Fat King/ Fat Kong
Spoke: Sapim CX-RAY
Nipple: Sapim Polyax Secure Lock
Each wheel from Light Bicycle is built using the best industry practices by professional builders, ensuring your investment stands the test of time.
Super Light Single-Wall Structural Design
The FS680 drops more than a 100g from our traditional double wall carbon rims by moving to a single wall design with our Flyweight technology, which uses a lighter pre-preg and a blend of Toray T800 and T700 carbon fiber.
Single-wall engineering is about more than just weight savings. By allowing the rim to flex vertically on impact, the design offers a stronger and more comfortable ride experience compared to double wall rims.
Precisely Reinforced Spoke Hole
Thanks to a special mold design and molding process, each spoke hole is accurately reinforced. This means that the area around the holes thickens to 3mm, allowing for the use of spokes at high tension without the need of a washer. This reinforced spoke hole has been tested on the new FS680 up to 300kgf without failure - far more than that our recommended 100-115kgf spoke tension.
Precisely Angled Spoke Holes
The ideal angle for spoke holes is 7°. By drilling the holes at these angles, the build process is improved by reduced stress at the nipple/spoke interface.
Special Foamed Material Used for Building
Instead of using an air bladder, we apply a lightweight foam material to build the shape of the cavity on both sides of the rim. Unlike a bladder, the foam material provides dampening and remains inside the rim after the manufacturing process is complete. Because no holes are required to remove the foam, the continuous strength of the carbon fiber is maintained.
Tubeless Compatible with A Wide Range of Tire Sizes
By using a slope design on the bead, the FS680 allows for easier tubeless tire installation and provides a better seal between the rim and tire. The shape of the bead seat reduces the chance of a tire burping at low pressure.
With a 80mm internal width, you can run anything from a standard 3.8″ fatbike tire to the massive and increasingly popular 5.0″ tires.
We’ve maintained a smooth exterior which is designed to prevent mud, sand or snow accumulation when riding, cutting down on any unnecessary weight or drag.
Our hookless design has consistent carbon compaction and there are no voids in the layup, providing the rim with a greater capability to withstand sharp impacts.