29er Carbon MTB Rim – 36mm Outer / 30mm Inner Wide, Wave Profile, 20mm & 25mm, 28-Spoke, 300–380g | Bola

29er Carbon MTB Rim – Wave Profile, 30mm Inner Wide (Bola)

The Bola 29er carbon MTB rim delivers a 36mm outer / 30mm inner width with a proprietary wave (wavy) profile in 20mm and 25mm heights, tuned for 28-spoke lacing. Four weight tiers — 380g, 350g, 325g, and 300g — let riders match rim mass to discipline without changing geometry or spoke count.

Specifications

Weight Tiers

Structural Strength Data

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

Tradeoff note: Moving from the 380g Standard tier to the 300g Extreme Light tier reduces rim mass by ~21% but narrows the safety margin for aggressive rock-garden impacts. Riders over 90 kg or running tubeless at the pressure ceiling (65 psi) are advised to select the Standard or Superlight grade.

Profile Selection Guide

• 20mm wave profile: Lower aerodynamic drag, lighter feel — suited to cross-country (XC) and marathon racing where rolling resistance and acceleration matter most.
• 25mm wave profile: Marginally stiffer lateral platform — better suited to trail and light enduro where cornering precision is prioritised over outright weight.

Compatibility

• Tyre compatibility: 2.0–2.6 inch MTB tyres (tubeless-ready with 30mm inner width)
• Spoke lacing: 28-hole; compatible with standard J-bend and straight-pull spokes at 4.5mm spoke hole diameter
• Valve: Presta (6.5mm hole); Schrader adapter not compatible without re-drilling

Frequently Asked Questions

Is a 30mm inner wide carbon rim better for aggressive MTB riding than standard width?

Yes. A 30mm inner width seats tyres 2.2–2.6 inch in a wider, rounder profile, improving cornering traction and reducing pinch-flat risk versus a 25mm inner width rim. It meets ETRTO recommendations for modern 29er MTB tyres sized 2.35 and above.

What is the lightest 29er carbon MTB rim available in this range?

The Extreme Light grade weighs 300 ± 10g per rim. At 290g minimum, it is among the lightest production carbon 29er rims at 36mm outer width. Note the tighter tolerance and the rider-weight guideline of <120 kg applies to all grades.

Should I choose the 20mm or 25mm profile for cross-country versus enduro?

Choose the 20mm profile for XC and marathon — lower profile reduces weight and aerodynamic drag at speed. Choose the 25mm profile for trail and enduro — the taller sidewall adds lateral stiffness under cornering loads.

What are the strength and weight tradeoffs between ultralight and standard carbon MTB rims?

The Standard grade (380g) maintains full structural margins across all three strength metrics. Each lighter tier reduces wall thickness incrementally; forward compressive and spoke tension figures remain >300 kg and >280 kg respectively across all grades per Bola's internal testing, but real-world impact resistance decreases as mass drops.

Can this rim be set up tubeless?

Yes. The 30mm inner width and 4.5mm spoke holes are compatible with standard tubeless tape and valves. Apply at least two full wraps of 33mm tubeless tape to ensure an airtight seal before installing a tubeless valve.