Although very rare, sometimes the spline nut is broken or loose. This guide explains how to replace and tighten the spline nut on 135mm solid axle hubs.

148mm modular axle hubs do not need this guide

Tightening the spline nut as explained in this guide is not applicable to 148mm modular axle hubs, as in such hubs the spline nut is integrated and does not need to be tightened.

Backward compatibility

This guide is compatible with legacy enviolo Commercial (CO), and NuVinci N360, N380, and N380SE hubs.

Video instructions

Step-by-step instructions

Use the spline nut tool

Be careful not to damage the spline nut. Make sure to use only the recommended enviolo spline nut tool to tighten the new spline nut.

Tools

• 10mm torque wrench
• Vice
• 44T spline nut
• Spline nut tool

Replacement instructions

1. Mount the wheel, clamping the left axle (brake) side in a vice.
2. Rotate counterclockwise to remove the old spline nut from the axle.
3. Place a new spline nut onto the axle.
   • Make sure to only use the Spline Nut tool (see image above) for the spline nut reassembly procedure.
   • Torque it to 8Nm approximately.
     
     

If wheel lacing is next

If this repair is done before the wheel lacing, then place the anti-shift retainer immediately back onto the axle.

Your spline nut is ready

If you successfully followed the steps above, then the spline nut is refitted.