Universal Rear Axle Chain Keeper - Bike Maintenance

Universal Rear Axle Chain Keeper Pulley

This 3D printable chain keeper is designed to hold the bicycle drivetrain under tension while the rear wheel is removed. It makes cleaning, lubricating and servicing the chain and rear derailleur much easier by allowing the drivetrain to rotate freely without the wheel installed.

The pulley mounts directly on the rear axle (thru axle or quick release, depending on the version) and provides a smooth, low-friction surface for the chain. Unlike a toothed sprocket, the groove is designed to work with the chain rollers, making it compatible with most modern drivetrains from Shimano, SRAM and KMC.

Features

• Universal design for most bicycles

• Compatible with Shimano, SRAM and KMC chains

• Suitable for road, gravel and MTB bikes

• Lightweight construction with reinforced outer rim

• Easy to print without supports

• Optimized for PETG, but also printable in PLA or ASA

• Smooth groove to minimize chain friction during maintenance

Recommended print settings

• Layer height: 0.20 mm

• 4–5 perimeters

• 25–40% infill (Gyroid or Grid)

• No supports required

• Print flat on the bed

PETG is recommended for better wear resistance and durability.

If you adapt the center hole diameter, the same design can be used with both thru axle and quick-release systems.

This tool is intended exclusively for bicycle maintenance. It is not designed to support riding loads and must never be used while riding the bicycle.

If you like this project, please consider leaving a like. It really helps and motivates me to create and share more designs.

If you print it, I'd also appreciate your feedback. Let me know how it fits, how it performs, and if you think there are any improvements that could make the design even better. Your suggestions are always welcome!