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Bola 700C 50mm Aero Carbon Clincher Rim | 25mm Wide Rim Brake

Bola 700C 50mm Aero Carbon Clincher Rim | 25mm Wide Rim Brake

$310.00 USD
$350.00 USD $310.00 USD
Sale Sold out
Free shipping  |  VAT included in EU & USA
Weave
Spoke QTY
Weight

The Bola 700C 50mm U-shape carbon clincher rim - a narrow 25mm-wide rim-brake clincher (NOT tubeless) for aero road and time-trial builds on caliper brakes.

Reach higher speeds on long straights, composed in the crosswinds: the Bola 50mm clincher rim pairs a 50mm aero profile with a narrow 25mm outer width for modern rim-brake road setups. Fifty millimetres of carbon, 25mm wide, sold rim-only.

Buying Guide.

Weight tier - lightest layup ~370g: the rim-brake racer's pick - lightest end for a classic caliper aero wheel.

Weight tier - heavier layup ~460g: the durable choice - more layup margin for training miles and heavier riders.

Max rider weight: rated to 120kg - check rider + gear before ordering.

Same-depth series: the 50mm road/gravel rim is the tubeless wide version; the 50mm tubular is the glued race option.

Adjacent depth: the 88mm TT rim goes deeper; the 60mm U-shape tubeless is the disc-brake deep-aero option.

Target Audience & Usage Notes.

Target audience.: Rim-brake road racers and TT riders on caliper brakes.

Rim-only.

This is clincher-only, NOT tubeless - run a tube.

Use carbon-specific rim-brake pads and manage heat on long descents; respect 125 psi and 120kg.

Not for tubeless or disc-brake builds.

The Ride That Awaits.

Lace it to a rim-brake road hub, fit a 28c clincher with a tube, and the 50mm U-profile carries you down the classic road: caliper-brake precision, aero where it counts, the old-school ride made new again. For the rider who still runs rim brakes. Free shipping, a 3-year rim warranty and crash-replacement discount.

Specifications
Size: 700c
Material: Genius Toray carbon fiber
Rim Depth: 50mm
Bead Type: Hooked
Inner Width: 18mm
Outer Width: 25mm
ERD (Effective Rim Diameter): 538mm
Weight Tier: 370-460g
Trade-offs & Considerations
Aero vs Crosswind: At 50mm depth this rim saves about 4.5W versus a 35mm rim at 40km/h, but the narrow 25mm outer width leaves a taller section; at 10° yaw it catches more crosswind than a 40mm rim on exposed descents.
Weight vs Stiffness: The lightest tier (about 370g) saves about 90g versus the standard tier (about 460g) (±5g) at the same 50mm depth; lateral stiffness holds within 3% across tiers, as the rim bed and spoke-flange geometry are unchanged.
Tire-Type Trade-off: This is a clincher rim with an inner tube: it runs a normal tube and clincher tyre from about 25c to 32c, so it cannot be sealed tubeless; the trade-off is simpler mounting and compatibility with any clincher, in exchange for the slightly higher rolling resistance and weight of a tube.
Sourcing & Delivery Trade-off: Stock drilling ships in 1–3 business days at $310; custom spoke-hole count, valve position or decals add 7–15 business days and roughly a $40–80 premium.
Performance Test Data
Fatigue Test: 750,000 cycles @640N (ISO 4210-7 Annex A, informative only)
Impact Resistance: >60J (Higher than ISO 4210-7)
Flatness: <0.15mm (internal QC)
Roundness: <0.3mm (internal QC)
Max Spoke Tension: >350 kgf (internal QC, spoke breaking tension)
Ultimate Strength: >300 kgf (internal QC, static spoke-hole point load)
Dynamic Equilibrium: <3g (internal QC)
Radial Stiffness: 90–110 N/mm (internal lab)
Lateral Stiffness: ≥8N/mm
Max System Weight: 120kgs
Recommended Use Cases
Sprinting / Criterium: Good: Aero profile helps maintain speed in breakaways and sprints, but weight penalty is noticeable on short, punchy climbs.
Triathlon / TT: Excellent: 50mm depth and U-shape provide significant aerodynamic advantage against the clock.
Road Racing: Excellent: Balanced aero and stiffness for fast flat and rolling courses, with stable handling in crosswinds.
Gran Fondo / Endurance: Suitable: Wide internal width allows comfortable tire choices, but deep section may feel heavy on long climbs.
Climbing / Hill Repeats: Not recommended: 50mm depth adds rotating weight that hinders acceleration and climbing efficiency.
Not Recommended For: Technical descents with strong crosswinds or highly mountainous races where weight is critical.
Compatibility
Frame Compatibility: 700C road frames with clearances for 21-30mm tires and rim brakes.
Tire Type: Clincher only (not tubeless compatible)
Tire Width Range: 21-30mm (optimal 28mm)
Brake Standard: Rim brake (caliper or cantilever with sufficient reach for 50mm depth)
Drivetrain: Compatible with standard road drivetrains (Shimano, SRAM, Campagnolo)
Rotor Standard: N/A (rim brake only)
How It Compares
ModelWeightDepthWidthPrice
700C 50mm Rim 25mm 370-460g 50mm 25mm See store
Model A ~430g 50mm 28mm $1,399
Model B ~420g 50mm 30mm $389
Model C ~430g 50mm 27mm $249
FAQ
What spoke drillings are available, and which brake type is this rim rated for?
Spoke drillings and brake rating depend on the build option, selectable at checkout. If you plan to lace your own wheel, confirm the drilling and brake type with Bola before ordering so the rim matches your hub and frame.
What is the maximum spoke tension for this rim?
Drive-side / disc-side max tension is 130–140 kgf, with the non-drive side adapted to match; spoke holes are locally reinforced inside the carbon layup to prevent pull-out cracking.
How does this deep rim handle crosswinds at speed, and is it stable on descents?
The aerodynamic profile keeps steering torque predictable at 10°–15° yaw — the rim stays planted at speed in steady-state crosswinds, with slightly more steering input in gusty conditions than a shallower rim.
What tyres can I mount on this rim, and what pressure should I run?
This is a clincher-only rim with an 18mm inner width: mount 25mm to 32mm clincher tyres with an inner tube, 28mm being the sweet spot. Tubeless tyres are not intended here.
Will I really pay no customs or VAT for delivery to the US and EU?
Yes. The Economy channel ships DDP — duties and VAT are fully prepaid by us, cleared in advance, delivered to your door with no extra payment to customs or the courier.
Warranty & Shipping
Warranty Period: 3 years
Crash Replacement: 30% discount on replacement parts
Processing Time: In stock: 1–3 business days · Out of stock or custom order: 7–15 business days
Shipping method: FedEx/UPS/DPD/EMS Economy (free with duties & VAT included in USA & EU) · Expedited option available
Estimated Delivery: Economy 7–20 business days · Expedited 3–7 business days, customs clearance excluded
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