With the release of our Execute XQ11, Eric shares with us the first option part he recommends upgrading to: the aluminum uprights (XP-11116,XP-11117) 

Eric recommends preparing: Loctite, Spray Cleaner (Cleaning Gum if not accessible)

Use spray cleaner or cleaning gum to clean off machining oil residue on the set screw.

Also clean the screw hole at the bottom of the aluminum upright.

Add loctite to the bottom half of the set screw.

When installing the set screw, make sure it does not stick out or it may hit the axle.

Loctite requires some time to dry, add the 0.5mm shim to the bottom.

Before installing to the arm, add some loctite to the set screw thread.

Picture of the completed assembly, the 0.5mm shim is used to obtain the same height as the plastic cups. Remove to gain more traction.