• Bola 700c 45mm Carbon Road Rim – 34mm Outer, 28mm Inner, Tubeless Ready
1 3

700C 50mm Asymmetric Carbon Rim 38/32mm Wide | Bola

700C 50mm Asymmetric Carbon Rim 38/32mm Wide | Bola

$340.00 USD
$400.00 USD $340.00 USD
Sale Sold out
Free shipping  |  VAT included in EU & USA
Weave
Spoke QTY
Weight

The Bola 700C 50mm asymmetric wide carbon rim (38mm external, 32mm internal) is a tubeless-ready rim for custom builds in aero road and wide-tire applications.

The wide asymmetric canvas: build your dream wheel. The Bola 700C 50mm asymmetric wide carbon rim is a builder's canvas — a 50mm deep, 38mm external, 32mm internal tubeless-ready rim with an asymmetric spoke bed that equalizes drive-side tension, offered in four weight tiers from 500g to 410g.

Buying Guide.

Weight tier - Standard ~500g: Heavy/Durable band - forgiving and impact-tolerant for training, rougher roads and larger riders who want margin.

Weight tier - Superlight ~470g: Midweight band - lively for rolling hills and sprints while still carrying the aero section comfortably.

Weight tier - Ultralight ~435g: light band - peppy acceleration for fast all-road riders on smoother terrain.

Weight tier - Extreme Light ~410g: ultralight band - climbing-responsive and razor-accelerating, best for lighter riders and clean roads.

Max rider weight: the build is rated to 120kg - match your chosen tier to rider weight and terrain.

Same-depth series: the PRM 50R (~$888), PRO 50R (~$999) and EXP 50R (~$999) are complete built wheelsets at this depth; this rim lets you spec your own hub and spokes.

Adjacent depth: 45mm Bola rims sit calmer in crosswinds and 60mm rims push aero further on flat, straight courses.

Target Audience & Usage Notes.

Rim-only product — hub, spokes, nipples and tape not included.

Requires at least 40mm frame/fork clearance for the 38mm external width.

Max rider weight 120kg; the Extreme Light tier is for lighter riders and smooth roads.

For experienced wheelbuilders only.

The Ride That Awaits.

Build it your way and the wide asymmetric rim beds a thick tire with a reassuring thud - stand on the pedals and the true, stiff build sings through the descents, the aero section slicing clean past the bars. Start with this rim and your dream wheel is already half-done. Free shipping and a 3-year rim warranty mean the only question is which hub to dream with.

Specifications
Size: 700c
Material: Genius Toray carbon fiber
Rim Depth: 50mm
Bead Type: Hooked
Inner Width: 32mm
Outer Width: 38mm
ERD (Effective Rim Diameter): 538
Weight Tier: 410-500g per rim (ST 500 / SL 470 / UL 435 / EL 410)
Trade-offs & Considerations
Aero vs Crosswind: 50mm depth saves about 4.5W versus a 35mm rim at 40km/h; at 10° yaw the 38mm outer width produces the strongest crosswind signature in this set, so expect real steering effort on exposed descents — a trade for the wider aero profile.
Weight vs Stiffness: The Extreme Light tier (410g) saves about 90g versus the Standard tier (500g) at the same 50mm depth (±5g); lateral stiffness holds within 4% across tiers, so the lightest layup keeps the same asymmetric bed.
Tire-Type Trade-off: The hooked bead runs clincher or tubeless tyres suited to the 32mm inner width (roughly 32–45mm) and is pressure-capped around 90psi; tubeless lowers rolling resistance but needs tape, valve and sealant.
Sourcing & Delivery Trade-off: Stock drilling ships in 1–3 business days at $340; a custom spoke-hole count, valve bore or nipple direction adds 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: <0.25mm (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: 80–92 N/mm (internal lab)
Lateral Stiffness: 16–23 N/mm
Max System Weight: 120kg
Recommended Use Cases
Road Racing Builds: 2026 peloton standard is 28-30mm tubeless on wide rims (TdF 2026 avg ≈30mm); 50mm section suits 40+ km/h racing.
Gran Fondo / Endurance: Modern 2026 frames (Propel, SuperSix, S5) design around 30-32mm clearance; 21mm inner bed pairs 25-32mm tubeless per ETRTO 2026 guidance.
Wheel Building: Custom road builds with disc or rim hubs; UD carbon layup options for weight-conscious or durable builds.
Weight Tier Selection: Offered in weight tiers (120kg rider); lighter for climbing, heavier for training and impact margin.
Compatibility
Product Type: Rim-only — no hub, spokes, nipples or tape included
Frame Clearance: Requires at least 40mm frame/fork clearance for 38mm external width
Tire: Tubeless-ready, 37-52mm recommended (6.5mm valve stem)
Spoke Holes: 20/20, configurable valve/spoke-hole diameters
Drivetrain: Not applicable — rim only
How It Compares
ModelWeightDepthWidthPrice
700C 50mm Rim 38mm 410-500g per rim (ST 500 / SL 470 / UL 435 / EL 410) 50mm 38mm See store
Model A ~430g 50mm 28mm $1,399
Model B ~430g 50mm 27mm $249
Model C ~420g 50mm 30mm $389
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.
Will the rim crack on rock gardens or bottom-outs at low pressure?
The rim bead area uses a thickened impact-reinforced layer; impact testing passes >60J extreme impacts (above the ISO 30J standard). Inner widths of 32mm accept wider tyres, which deform to absorb shock at low pressure.
What tyres can I mount on this rim, and what pressure should I run?
The 32mm inner width suits tyres from 32mm to 37mm, with a 90psi maximum; run lower pressures off-road for gravel cushioning.
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
View full details