Bike porn

Looks like nothing; no bearing cover, not even a thin one. Not the first pro bike to have been seen like this, since the frame manufacturers have moved to long head tubes for the Fred/Sportive market and can't do proper race frames for proper racers because the UCI sticker costs $12k

Looks like a mod of some kind at least.

Maybe the 'Sportive' types should be given Argon18 style extendable headtubes.