Elevate Your Ride, Embrace the Road
Born for disc brake, the DB405 UltraDark and DB508 UltraDark have first-class performance, with lower front and higher rear rim height design. The new dark black design goes with versatile frames.Upgrade of hub and spokes even provides faster and more stable response, making the wheelset an optimal choice for performance pursuers.
Features
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Classy Night Black Finish
Featuring a sleek night black matte paint coating paired with understated dark logos, delivering a sophisticated aesthetic that seamlessly complements any bike frame.
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Ceramic Bearings & Precision Hub
Equipped with high-performance ceramic bearings for ultra-low rolling resistance and maximum drivetrain efficiency. The hub features optimized flange diameters and smooth bearing seating to minimize rotational friction and extend longevity.
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HI-MOD Carbon Fiber & Carbon Spokes
Built with high-modulus carbon fiber rims and VONOA carbon fiber spokes (weighing just 2.8g per spoke—30% lighter and 30% stronger than top-tier steel spokes), significantly reducing rotational weight for explosive climbing and acceleration response.
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Lower Front and Higher Rear Aerodynamic Profile
Combines a lower front wheel for superior steering agility and crosswind control with a higher rear wheel for sustained high-speed inertia and aerodynamic efficiency.
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30mm Wide Fat Rim Design
Engineered strictly for disc brakes with a 30mm external and 23mm internal width. Optimized for 28c–32c tires to create a smoother, flush transition profile that enhances aerodynamics and ride comfort.
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36T Flat Engagement Ratchet
Delivers stable, reliable power engagement at all speeds. The 36T flat ratchet is fully compatible with DT Swiss-style systems, allowing you to easily swap ratchets to customize engagement speed.
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2:1 Balanced Lacing & Precision Hub
Features a 2:1 balanced spoke lacing pattern (130kgf drive-side / 110kgf non-drive-side) to perfectly distribute tension and double structural stability. The hub features optimized flange diameters and smooth bearing seating to minimize rotational friction.
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Tubeless & Clincher Compatibility
Fully compatible with both conventional clinchers and tubeless setups. Includes tubeless rim tape, valves, and 50 rim hole plugs (which can replace rim tape for extra weight savings when running clinchers).
Specifications
| Specification | DB405 UltraDark | DB508 UltraDark |
| Rim Height | Front 40mm / Rear 45mm | Front 50mm / Rear 58mm |
| Weight | 1305g (±3%, excl. tape & valves) | 1390g (±3%, excl. tape & valves) |
| External / Internal Width | External 30mm / Internal 23mm | External 30mm / Internal 23mm |
| Rim Material | HI-MOD Carbon Fiber | HI-MOD Carbon Fiber |
| Brake Type | Centerlock Disc Brake | Centerlock Disc Brake |
| Bearings | Ceramic Bearings | Ceramic Bearings |
| Spokes | VONOA HI-MOD Carbon Fiber | VONOA HI-MOD Carbon Fiber |
| Spoke Lacing Pattern | Front 21H (2:1) / Rear 21H (2:1) | Front 21H (2:1) / Rear 21H (2:1) |
| Freehub / Ratchet | 36T Flat Ratchet (DT System Compatible) | 36T Flat Ratchet (DT System Compatible) |
| Freehub Compatibility |
Standard Shimano 11/12-speed (SRAM XDR / Campagnolo N3W sold separately) |
Standard Shimano 11/12-speed (SRAM XDR / Campagnolo N3W sold separately) |
| Axle Spacing | Front 12×100mm / Rear 12×142mm Thru-Axle | Front 12×100mm / Rear 12×142mm Thru-Axle |
| Compatible Tire Types | Clincher, Tubeless | Clincher, Tubeless |
| Suggested Tire Width | 28c – 32c (Compatible with 25c+) | 28c – 32c (Compatible with 25c+) |
| Max Tire Pressure | Clincher: 110 psi / Tubeless: 100 psi | Clincher: 110 psi / Tubeless: 100 psi |
WARRANTY POLICY
We stand behind the quality and craftsmanship of EXAR wheelsets. Our products are covered by a Limited Warranty under the following terms:
1. Warranty Coverage & Duration
• Carbon Rims: Covered by a 2-Year Limited Warranty from the date of original purchase against manufacturing defects in materials and workmanship.
• Hubs, Spokes, and Bearings: Covered by a 1-Year Limited Warranty from the date of original purchase against manufacturing defects in materials and workmanship.
2. Exclusions & What Is Not Covered
This warranty applies strictly to manufacturing defects and does NOT cover:
• Damage caused by crashes, accidents, impacts, or severe external forces.
• Damage resulting from improper tire installation, incorrect tire pressure, or misuse.
• Normal wear and tear (including brake track wear, cosmetic fading, or minor scratches).
• Damage caused by improper installation, improper maintenance, unauthorized modification, or neglect.