Bola 700c Carbon Gravel Rim 40mm High | 30mm Wide | 325–395g | Hooked or Hookless Tubeless

Bola 700c Carbon Gravel Rim — 40mm Profile, 30mm Outer Width, Tubeless Ready

The Bola 700c carbon gravel rim delivers a 40mm aerodynamic profile and a 30mm outer width optimised for mixed-terrain gravel riding. Available in four weight tiers — from a standard 395g down to an extreme-light 325g per rim — it supports both hooked (24mm inner width) and hookless (25mm inner width) tubeless configurations to suit a wide range of gravel tire setups from 38c to 50c.

Key Specifications

Weight Variants

Structural Strength Testing

• Forward Compressive Strength: >300 kg
• Lateral Torsion: >50 kg
• Spoke Hole Tension: >280 kg

Hooked vs. Hookless — Which Should You Choose?

Hooked (24mm inner width): Compatible with a broader range of clincher and tubeless tires, including older tire standards. Recommended if you use multiple tire brands or frequently swap between clincher and tubeless setups.

Hookless (25mm inner width): The 25mm internal width pairs optimally with modern tubeless gravel tires (38c–50c), reduces rim weight slightly, and improves rim-to-tire air seal consistency. Note: hookless rims require ETRTO-compliant tubeless tires and a maximum tire pressure of 73 psi per ETRTO 2023 hookless guidelines — verify your tire manufacturer's compatibility before building.

Rim Width and Tire Performance

A 30mm outer / 24–25mm inner width is designed for gravel tires in the 38c–50c range. Wider inner rims reduce tire sidewall pinch, improve cornering stability, and support lower tire pressures for better compliance on loose or mixed-terrain surfaces. Running a 40c tire on this rim yields an effective mounted width approximately 2–3mm wider than the labeled tire size.

Known Tradeoffs

• The extreme-light 325g tier prioritises minimum weight; riders over 80 kg or those riding aggressive rocky terrain may prefer the standard (395g) or superlight (365g) tier for added durability margin.
• Maximum tire pressure is capped at 125 psi (hooked) — not suitable for high-pressure road clincher applications.
• Rider weight limit is ≤100 kg including rider, clothing, and kit.

Frequently Asked Questions

Are these rims compatible with rim-brake setups?

No. These are disc-brake-only rims with no braking surface. They are designed exclusively for disc brake gravel and road disc builds.

What is the lightest option available?

The Extreme Light tier weighs 325 ± 10g per rim, making it one of the lightest 700c carbon gravel rims in the 40mm profile category. This tier is best suited to riders under 75 kg on moderate gravel terrain.

Can I run tubeless without tape?

No. These rims require tubeless rim tape and a compatible tubeless valve. The spoke bed is not fully sealed from the factory; standard tubeless tape and sealant setup applies.

What spoke counts are available?

Spoke hole counts and drilling patterns are available in standard configurations or custom options — contact Bola directly to confirm available drillings for your hub specification.

Is a warranty included?

Yes. Bola offers a three-year warranty covering manufacturing defects under normal use conditions.