So, what's the proper method to wash one's helmet? We asked a couple of helmet industry insiders, and their answers are a lot simpler than you might imagine. Arai recommends immersing your lid completely in soapy water, shampoo being a good bet as it's mild yet good at dissolving the dirt and oils that collect on the comfort liner. Shoei espouses a similar method, though it specifically recommends Woolite. Most of Arai's and Shoei's current helmets have removable liners, which make cleaning a much easier affair as they can simply be removed and dunked. Helmets with non-removable liners must be completely immersed. A word of warning: Although Arai and Shoei use adhesives that aren't affected by water, other helmets may not be so designed. Check with the manufacturer if you're unsure.