Karl, I've got both an AIROH Mathisse and a SHARK RSi, from time to time I remove the soft inner linings and soak them in soapwater, clean the hard shell also with a cloth soaked in the same soapsolution, then rinse the innards with clean water and hang them out to dry in the shade, gives you a clean helmet and a good smell too. Many of us do the mistake in not hanging the helmets somewhere to dry after usage (not to be exposed to the sun directly). I always take them into my A/C living rooms where they dry quickly and don't smell too much. Worst thing, I left them in my topcase, metal parts started to rust after several days.....sorry but there's no good sprays to my knowledge, you won't be spared the job of thorough washing from time to time, cheers, Franz
