>>1194342if you notice skipping when you mash, something (or everything) on your drivetrain is worn.
you can measure the chain with a tool, if you notice extreme side-play when you have it off the bike, that's a "ballpark" sign.
gears you can just look at. brand new teeth will still look squared-off on the "points." when they are closer to actual points, they're blown. sharkteeth means they already should have been replaced.
in pic, the middle ring is mostly sharktoothed and needs to go. the big ring is showing some wear but the extreme left tooth looks pretty perfect. the small ring you can't see but doesn't look like they use it much so it's probably in great shape.
