Clanking sound from the bottom bracket when I pedal My MTB, having not received much TLC lately, was making a lot of squeaks and noises.
After a long-overdue clean-up and lubrication of the drivetrain, most have gone away.
However there's something still making clicking (?) noises, and it seems to come from the bottom bracket area.
It only happens when I pedal, regardless if I use a lot of force or not, but not for super-light action - like pedalling by hand, with the bike on a stand.
See (and hear) this video.
Any suggestions to what may be causing this?
My first suspicion is the chain hitting the front derailleur cage. The clicking is fairly loud and occurs continuously whenever you pedal. If the bottom bracket bearings were damaged you would feel it through the cranks rather than hearing it and there would be clicks once per crank rotation.
It's also possible that you have chainsuck going on. A worn chainring can hold on to chain links past the point where they should disengage, then they pop off the chainring teeth with a click.
Put the bike in a workstand (or have a friend hold the back wheel of the ground), pedal manually and inspect the crank area to see where the noise is coming from. Try different gear combination to see if that makes a difference.
You can also check the bottom bracket bearings - turn the crank by hand and feel for clicks or 'notchiness'. Push and pull the cranks to check for any play in the bearings.