I take my chain off to clean, yes, I am picky. What I have noticed is the speed and tension sensors have magnetized my chain, making it harder to clean since the majority of the dirt is powdered chain, which being steel, is attracted to the chain and difficult to remove.

The chain can become strongly manetic to the point the free ends will stay together for 3-4 inches of arc.

I made a degausser with a coil of insulated wire and a lightbulb in series to limit current. This works well, making cleaning a one step process in my ultrasonic cleaner. Before degaussing, it took 4-6 washings until the cleaning fluid ran clear.

Success! After implementing degaussing before cleaning, it now takes only two washings in deodorized mineral spirits to end up with a perfectly clean chain. Since I filter and recycle the mineral spirits, I recover magnetic debris using a spare cadence magnet. The majority of the metal is probably harmless as it is in suspension, indicating sub-micron size particles. The filter will not remove these particles which give the solvent a greyish tint. A few hours of the magnet clears the solvent, resulting a a very fine grey powder on the magnet.

I think with this procedure and an accurate milligram scale, I could conduct meaningful wear tests on chain lube.