Earth Strap

I have my 2008 T100 on the bench going through it and I am checking various things, connections secure , bolts tight etc. I wanted to check the cleanliness and tightness of the main earthing strap from the battery, for the life of me I cannot find the end of the connection that connects to the engine.

There are the two earth wires that come from the single ring connector, both have good connectivity when tested against engine and frame, one larger, which I assume is the main earth and a smaller dia. one which looks as though it disappears into the loom, I can trace the larger one a few inches then it disappears down the spine in front of the battery at the air box, can anyone tell me where the opposite end from the battery is attached to?, it seems to have done an 'Alice' and disappeared down a hole!