Bossi Core SL Carbon wheelset

The Core SL is our most advanced road wheelset to date. Lightweight, responsive, and built to last.

The SL combines a new carbon layup, ceramic bearings, and ultra-light unidirectional carbon spokes into a package that’s both lightweight and remarkably resilient.

At just 1275 grams, the Core SL shaves meaningful rotational mass, delivering sharper acceleration and greater responsiveness under load. Its 50mm rim depth strikes a balance between aerodynamic efficiency and predictable handling, while the 23mm internal width pairs seamlessly with wider tyre profiles to enhance aerodynamics and grip. The hooked rim design ensures broad tyre compatibility and easy tubeless setup.

What sets the Core SL apart is its spoke system. We’ve developed new UD carbon spokes specifically for this wheelset, engineered to improve lateral stiffness while significantly reducing weight. Compared to a traditional steel build, the result is over 200 grams saved and a tighter, more reactive ride feel that rewards every effort.

At the centre is the new Bossi Core SL hubset, equipped with TPI ceramic bearings for reduced rolling resistance and lasting durability. The spoke layout—20 front, 24 rear is optimised for a balance of strength, stiffness, and weight. Like every Bossi wheelset, the Core SL is hand-built to exacting tolerances for consistency you can count on.

Visually, the UD marble finish is subtle but distinct. No two sets are identical. The natural variance in the layup reflects the bespoke nature of the product. Eye-catching. Purposeful. Design values that permeate all our products

The Core SL is designed for performance, but built for the long haul. It reflects everything we stand for: minimalist, functional, and quietly confident.

Technical Specification

RIM

• 50mm T800-T1000 carbon rim, tubeless ready

• 23mm hooked internal rim width (25mm wall to wall)

• 30.5mm external rim width, aerodynamically optimised for 28-30c tyres.

• Reinforced nipple hole patching

• Counterbalance balast patch opposite valve

• Laser engraved logos

• Marbled carbon finish

• 120 PSI max tyre pressure

• ERD = 539mm

HUB

• TPI Ceramic bearings front and rear

• Star ratchet, 45T, 8 degree engagement

• Rear lacing pattern - 24 spoke, 2:1, Cross 2 DS and NDS

• Front lacing pattern - 20 spoke, 1:1, Cross 2 DS and NDS

• 7075-T6 Forged alloy /heat treated hub body

• 7075-T6 CNC axles

WHEEL

• T1000 UD carbon bladed spokes, T head, threaded

• External nipple, black anodized

• 5 year warranty

• 120kg system limit

• 1275g +/- 15g