I want very high visibility gear when I ride.
Last year I tried machine wash, "hand-wash" cycle with very good soap (Persil)….without much luck in removing the road grime which builds up on my Hi Viz FirstGear armored riding jacket.
So, this year - into the tub ... Worked the jacket for nearly an hour with Persil and a med soft long bristle nylon brush.
Back into the machine for a rinse....then hung dry outdoors in the shade. Washed the 5 pads and their covers.
Very, very nice results. The work with the brush did the trick!
So, use good soap, and a med soft brush …..and invest nearly an hour!