The Project321 RG3 142x12 Rear Hub

The RG3 is Project321's new hub platform designed specifically for road and gravel riders who demand precision, speed, and durability across any road surface. Building on our proven M-Pulse Technology, RG3 delivers instant, rock-solid engagement, ultra-low drag, and unmatched reliability—whether you are hammering on smooth tarmac or grinding through unpredictable gravel terrain.

Project321’s reputation for toughness and innovation extends to the RG3 hubs, which deliver the same performance DNA to road and gravel riding. RG3 features a stiff axle and bearing platform, refined internal architecture, advanced sealing, and their game-changing 6-Lock rotor system, making it a truly versatile option for today's performance-driven riders.

Engagement

At the heart of the RG3 is Project321’s M-Pulse Technology, a magnetically actuated engagement system that delivers lightning-fast power transfer and exceptionally low drag.

Borrowing the 72-tooth drive ring and three-step magnetic pawl layout from their G3 mountain bike platform, the RG3 provides 144 Points of Engagement in its standard configuration—equating to just 2.50° of rotation. Riders seeking even faster response can upgrade to 288 POE, for a crisp 1.25° engagement angle.

Unlike traditional spring actuated drive mechanisms, M-Pulse uses magnets to actuate the pawls—eliminating tiny springs that can be lost or damaged during servicing. This not only reduces drag, but also improves reliability and ease of maintenance.

Learn more about the technology behind RG3.

Specifications:

• Axle Compatibility: 12x142 Rear (Thru-Axle Only)
• Driver Options: SRAM XDR, Shimano HG-Road, Shimano Microspline
• Engagement: 144 POE/2.50°, expandable to 288 POE/1.25°
• Weight for Pair: Starting at 370g

If you are experiencing issues with your Project 321 hubs and you feel you require warranty help, please use the link below to learn more.

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