The "I'm an idiot" Thread

[Yukonrider]

Bike was making horrendous bearing explody sounds when pedaling under load, but only in the easiest two gears.

Replaced a notchy idler pully bearing, didn't fix it.
Took it to the LBS to measure chain wear, chain is like new.
Bought new lube, cleaned chain thoroughly, didn't fix it.
Figured it would just explode and I would deal with it then, went on a few more rides and nothing happened besides me going crazy listening to the grinding.

Finally had an opportunity to wash the bike, noise is gone.

The bike was just dirty. WTF.

[toast2266]

I've had very small pebbles wedge themselves in weird places where they're captured and just kinda grind against some party of the drivetrain. Maybe something like that?

Sent from my SM-S901U using Tapatalk

[Yukonrider]

I've had very small pebbles wedge themselves in weird places where they're captured and just kinda grind against some party of the drivetrain. Maybe something like that?

Sent from my SM-S901U using Tapatalk

When I say washed the bike I really mean I sprayed the cassette with brake clean and scrubbed it with paper towels.
I was riding some pretty serious mud and stuff for a few days, but had never had a cassette get dirty and stay dirty. In my past experience cleaning the chain took care of most not obvious drive train sounds.
I've been traveling around with the bike behind the car for the last couple weeks so a real hose wash hasn't been an option.