The pictures are taken through the seattube of my 2019 BMC Teammachine SLR02. I can clearly see the bottle cage screws,the three rivets holding the front derailleur as well as the rear brake hose going over the BB sleeve. However behind the sleeve I see this weirdly shaped piece that does not seem to move when I shake the bike. It does not match anything on the outside of the frame except maybe the drain holes on the third picture. Could anyone help me stop scratching my head over this ?
by Apprehensive_Plum868
3 Comments
It’s something not user serviceable that you don’t need to worry about
99% most likely dirt. If nothings wrong why are you worrying?
it’s probably leftover material from the mold/weld.
they don’t polish the inside of the bike frame.