Valued Light Bicycle customer T.R. joined our product panel (learn more here) to stay informed when our latest ultra-climbing innovation, the UC25T, was in development. When the UC25C clincher version became available, T.R. was sold, and contacted us via email with his preferred configuration. He was on the hunt for a super-light, tubeless-compatible wheelset tailored for long, grueling hill climbs. He requested the complete wheelset weigh in at less than 900g.
“I really grew on Extralite products. Now, coming with Enduro Bearings - feels like a no brainer. Is it possible? Let me know what will be the best for my wheels!”
— — T.R.
Build Details
Rims: UC25C disc paintless UD 24H with access holes [Available for order offline]
Hubs: Extralite HyperSmart3 enduro bearings 12/100mm 12/142mm 48T Shimano Road 11s
Spokes: Light Bicycle Flyweight carbon (regular edition-butted)
Nipples: Sapim aluminum black & red (2 around valve & 2 opposite the valve)
Decal: Custom laser engraved graphics
Rider Profile
Name: T.R.
Origin: Israel
Weight: approximately 60kg
Tire: Tubeless
Wheel Idea: A super lightweight boutique wheelset, custom built by hand to handle ultra-endurance climbing challenges (24+ hours).
Our Flyweight carbon spokes have far less lateral resistance than their steel counterparts, making them extremely comfortable to ride, but vulnerable to bending. Using conventional spoke calculations and lacing methods with our Extralight hub proved to be problematic as we detected spoke bending during the build process, which can decrease the service life of the carbon spokes.
After careful investigation, we found that the drilling angle of the hub’s flange holes was slightly unusual. The angle difference likely had minimal impact when building with steel spokes, but was exacerbated when building with carbon.
The Challenges
To guarantee a durable wheel, our engineers and wheel builders worked on a solution overcoming the following challenges:
1. All-new lacing method: Considering the hub dimensions and spoke seat angles, we redesigned the lacing pattern. A traditional lacing pattern (evenly-spaced holes) was incompatible with Light Bicycle carbon spokes, so to fully align the carbon spokes between the hub hole and the rim hole, we approached things differently.
2. Layup adjustment: Our engineers adjusted the layup schedule for precise reinforcement around the drilling area. Uneven drilling can lead to imbalance, causing a wheel to come out of true easily, especially with lightweight products.
3. Retain lightweight character: Achieving desired performance and strength without compromising the primary appeal of ultra-light rims was one of our highest priorities.
Our Approach
After some rigorous testing, our team devised a complete wheel solution for the carbon spoke build.
1. G4 drilling: After iterating hole patterns, we determined the final drilling pattern. The result is a unique lacing pattern with four holes placed closely together, that we call “G4”.
2. New material: A G4 patterned wheel requires more inherent stiffness to keep the wheel true. We sourced a new roll of carbon prepregs with a higher strength-to-weight ratio to add stiffness.
3. New layup: To tackle concentrated tension, we optimized the reinforcement around the spoke holes with additional laminates. With the use of the new carbon material, our engineers fine-tuned the layup schedule to make the rims stiffer while maintaining weight.