What's a Torque Cap?
Torque Caps increase the contact face of the hub from 19mm to a whopping 31mm to increase front-end stiffness.
You can use a 'regular' 15mm thru-axle hub in a Torque Cap fork, however the correct Torque Caps will increase wheel stiffness and make installing the front wheel easier as the wheel will locate the thru-axle faster.
Rockshox is the primary manufacturer using Torque Caps and they have produced both 100mm non-Boost and 110mm Boost forks with Torque Caps.
Compatibility
These instructions are the same for either a Boost or Non-Boost hub shell.
The outcome of installing Torque Caps onto a non-Boost hub shell will be 100x15mm
The outcome of installing Torque Caps onto a Boost hub shell will be 110x15mm
Step 1: Removing existing endcaps
Remove the old endcaps. This is the hardest part of the job as the endcaps use a tapered seal to securely hold them in place and keep water out. Removing the endcap requires folding the V shaped seal back on itself.
Step 2: Installing the non-disc endcap
Push E28 onto the hub and check it’s fully seated on the bearing
Step 3: Installing the disc side endcap inner
Push the E01 section of the disc side endcap onto the hub and check it’s seated correctly against the bearing.
Step 4: Installing the disc rotor
Install the rotor and lockring as per the manufacturers instructions.
You will need to use the 'bottom bracket type' rather than 'cassette type' lockring.
Step 5: Installing the disc side endcap outer
Push the E30 endcap outer onto the E01 endcap inner.