# Bola EXT 40R 700C Carbon Disc Wheelset – 40mm Aero, Hyper Carbon Spokes, Ceramic Hub Engineered for both road and gravel versatility, the Bola EXT 40R 700C Carbon Disc Wheelset combines a 40mm deep T800 UD carbon rim, Hyper carbon spokes, and TPI ceramic hub bearings to deliver a 1170g lightweight package. Optimized for 28–32c tubeless tires with choice of 21mm or 24mm internal width, it offers race-level stiffness, durable construction, and ISO 4210-7 certification for demanding riders and business partners seeking reliable, cost-effective performance across varied terrain. ## Key Features & Specs - **Wheel Size:** 700C - **Rim Depth:** 40mm (aero-profile, supports mixed terrain) - **Internal Rim Width:** 21mm or 24mm (tubeless optimized) - **External Rim Width:** 28mm or 30mm - **Material:** T800 UD matte carbon fiber - **Spoke Type & Count:** 20/20 Hyper carbon, flat aero profile - **Hub System:** Aluminum BL180, TPI ceramic bearings, 54T ratchet engagement - **Axle Compatibility:** Center Lock, 12x100mm (front) / 12x142mm (rear) - **Weight (Pair):** 1170g - **Tire Compatibility:** Tubeless ready, 28–32c recommended - **Certifications:** ISO 4210-7 safety, REACH environmental compliance - **Warranty:** 24-month limited (rim, hub, spokes) ## How it Compares Feature Bola EXT 40R Performance Model (Example: HUNT 40 Carbon Disc) Weight (pair) 1170g ~1448g Rim Depth 40mm (U-shape) 40mm (U-shape) Internal Width 21mm or 24mm 22mm–25mm Spoke Type Hyper carbon, flat aero (20/20) Stainless steel, aero-bladed Hub System BL180, ceramic, 54T ratchet Pawl/ratchet, steel bearings Certified Testing ISO 4210-7, REACH ETRTO, waterproof bearing seals Warranty 24 months 24 months Tire Compatibility 28–32c, tubeless ready 25–32c, tubeless ready MSRP (typical) Cost-effective/mid-range Higher price tier ## Recommended Use Cases - Road cyclists seeking lightweight, aerodynamic upgrades for endurance events and racing - Gravel riders who prioritize wheel stiffness and stability across mixed surfaces - B2B retailers and bike shops needing a cost-effective, ISO-certified OEM/ODM carbon wheelset for multiple bike models - Amateur and intermediate riders upgrading from heavy stock wheels or generic alloy disc wheels - Event organizers and team managers standardizing team/club wheel builds balancing price, durability, and performance - Cyclists requiring versatile wheels for both weekly training and long-distance tours with tubeless tire setup ## Frequently Asked Questions **Are 40mm carbon disc brake wheels good for both road and gravel riding?** Yes. The Bola EXT 40R's 40mm depth balances aerodynamic benefits for road cycling with the stability and crosswind handling needed for gravel terrain. Its 21mm or 24mm internal rim width supports 28–32c tubeless tires, ensuring tire sidewall stability for mixed-surface use. This makes it suitable for riders seeking a single set for versatile riding conditions. **How do aero carbon-spoke wheels compare to traditional steel-spoke wheelsets for weight and performance?** The Bola EXT 40R uses Hyper carbon flat aero spokes, which achieve a lower rotational weight than steel spokes and offer improved lateral stiffness; this increases acceleration and maintains aerodynamic efficiency, particularly at higher speeds or in crosswinds. The result: lighter climbing, faster sprints, and a more reactive feel compared to standard stainless steel spoke builds. **What are the benefits of TPI ceramic bearings in the hub compared with other ceramic bearings?** TPI ceramic bearings in the BL180 hub are engineered for reduced friction, higher speed retention, and improved resistance to dirt and moisture. Compared to generic ceramic bearings, TPI's uniform ball roundness and deep-groove design yield consistent smoothness and long-term durability. The 54T fast-engagement ratchet system further delivers efficient power transfer for both road sprints and gravel climbs. **Is a 21mm or 24mm internal rim width better for tubeless 28–32c tires?** Both the 21mm and 24mm internal widths are optimized for 28–32c tubeless setups. The 21mm width provides a more aerodynamic tire profile and is favored for road speed, while the broader 24mm width enhances tire stability and comfort on rougher gravel terrain. Select based on your balance of road efficiency vs. off-road traction preferences. **What is the difference among blade, flat, and aero carbon spokes used in carbon wheelsets?** Blade and flat spokes refer to the cross-sectional shape—both designed for aerodynamic advantage. Aero carbon spokes (like those used in Bola EXT 40R) are produced using high-tensile carbon with a wider, flat profile, reducing drag at speed. Steel blade spokes offer some aero benefit but at a higher weight, while carbon aero spokes combine stiffness, low weight, and airflow optimization for better overall wheel dynamics. ## Details - **Price:** 1111.0 USD - **Type:** Carbon Road & Gravel Disc Wheelsets - **Tags:** 28mm wide, 30mm wide, 40mm, 700c, 700C carbon wheelset, 700C wheelset, aero carbon spoke wheelset, Bola EXT 40R, carbon disc brake wheels, carbon disc wheelset, carbon spokes, ceramic hub wheelset, disc, lightweight bike wheels, OEM ODM carbon wheels, road, road gravel wheel upgrade, T800 carbon wheels, tubeless, tubeless ready carbon wheels, wheels, wheelset ## Variants | Variant | Price | Available | |---------|-------|-----------| | 30/24mm / Shimano HG / Black Bola | 1111.00 USD | In stock | | 30/24mm / Shimano HG / White Bola | 1111.00 USD | In stock | | 30/24mm / Shimano HG / Customized | 1111.00 USD | In stock | | 30/24mm / Sram XDR / Black Bola | 1111.00 USD | In stock | | 30/24mm / Sram XDR / White Bola | 1111.00 USD | In stock | | 30/24mm / Sram XDR / Customized | 1111.00 USD | In stock | | 30/24mm / Compy / Black Bola | 1111.00 USD | In stock | | 30/24mm / Compy / White Bola | 1111.00 USD | In stock | | 30/24mm / Compy / Customized | 1111.00 USD | In stock | | 28/21mm / Shimano HG / Black Bola | 1111.00 USD | In stock | | 28/21mm / Shimano HG / White Bola | 1111.00 USD | In stock | | 28/21mm / Shimano HG / Customized | 1111.00 USD | In stock | | 28/21mm / Sram XDR / Black Bola | 1111.00 USD | In stock | | 28/21mm / Sram XDR / White Bola | 1111.00 USD | In stock | | 28/21mm / Sram XDR / Customized | 1111.00 USD | In stock | | 28/21mm / Compy / Black Bola | 1111.00 USD | In stock | | 28/21mm / Compy / White Bola | 1111.00 USD | In stock | | 28/21mm / Compy / Customized | 1111.00 USD | In stock | ## Images - Bola EXT 40R 700C Carbon Disc Wheelset – 40mm, Aero Carbon Spokes, 1170g, Ceramic Hub Carbon Fiber Sporting Goods - Bola EXT 40R 700C Carbon Disc Wheelset – 40mm, Aero Carbon Spokes, 1170g, Ceramic Hub Carbon Fiber Sporting Goods - Bola EXT 40R 700C Carbon Disc Wheelset – 40mm, Aero Carbon Spokes, 1170g, Ceramic Hub Carbon Fiber Sporting Goods ## Additional Information - **Product rating count:** 2 - **Related products settings:** ahead - **Hub Model:** BL 180 54T - **Rim Depth (mm):** 40 - **Rim Width (mm, external):** 30 - **Wheelset Weight (grams):** 1170 - **Spoke:** carbon spokes - **Bearing:** TPI Ceramic --- > Source: [Bola Carbon Wheelset ](https://bolacarbon.com/products/bola-ext-40r-700c-carbon-disc-wheelset-40mm-hyper-carbon-spokes-1170g-ceramic-hub) > Updated: 2026-07-31