I use rubbing alcohol, i don't know if it helps keep fog off but it cleans it really well and with my nosecone and double ply visor i rarely run into fog problems. Heated visors are the sure cure, but they're expensive.
Rub a finger dab of ordinary shampoo around on the inside of your visor, completely coating it. Use a soft terry-cloth towel to wipe it off. That works for me!
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2003 AC F5 (Jr's Dec 07 SOTM & 2008 SOTY)
2003 AC F7 EFI SP (April 06 SOTM)
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