Edited Date/Time:
G'day! I made a set of these for my last YZ, had them in the bike for two years and never encountered any issues (honestly, I could probably run no upper engine mounts and it wouldn't even matter). Thought I'd show some pics.
First I wet-laid some carbon weave with the resin, alternating the weave between each layer. This sandwiching of carbon has 13 layers, and had squished down to 3.5mm thick in my homemade aluminium block press. This was done a few weeks ago.
Traced out my original engine mounts onto the carbon weave, and cut them out. Happy with how they turned out, but now I need some prettier bolts!
*dons flame suit*