I have my ~2010 Surly LHT set up inside on a Wahoo Kickr Core smart trainer. The other day on an inside training ride I heard a 'thwang' and noticed this piece of metal on the floor below the bike. Anyone have any idea what it might be/what it came off? As far as I can tell the bike is riding fine, though the bike & drivetrain are older and don't exactly run smooth as butter to begin with. Thanks!
by notofthisearthworm
7 Comments
Looks like you may have a horse not a bike, and that is a horse shoe
Looks like the inside of a ball bearing where it stopped spinning and the balls slowly dug into the metal. Maybe from your rear hub?
Is your shifting still indexing normally? That looks like it might be an index ring (probably the wrong term) from a shifter.
Since you have an LHT I’m assuming you have bar end shifters. Is your rear shift indexing still working? That looks like an internal part of a Microshift shifter and there are small ball bearings that go into those holes for the indexing. See the EVs starting on page 26 here, about the middle of the exploded parts above the shifter:
https://www.microshift.com/wp-content/uploads/2021/01/SH001-002-Bar-End-Shifter-Manual.pdf
Since you remove the rear wheel to put your bike on the smart trainer, it rules out your bike’s rear wheel as the source of that fragment.
I would check the rear derailleur on your bike and the crank/BB to make sure nothing there is amiss. If that’s the case then that fragment came from your Kickr Core.
Headset bearing race?
They look like detents for something with 9 positions. A spring loaded ball would snap in to each position.