One rather annoying issue many motorcyclists face making it nearly impossible to ride happens when the fog rolls in and completely steams up the helmet shield.
Shield or visor fogging generally occurs when cold outside air temperatures meet the warm inside temperatures and moist air generated from your body and breath. Outside humidity also poses a problem and a visor can fog up even in warm temperatures (though not as likely) as long as the heat from your body and breath prove much warmer.
Once the visor starts to fog you have little in your arsenal to stop the madness until you pull off and wipe off the shield. But, a number of precautionary steps can prevent this problem from ever occurring so if you deal with a cloudy shield far too often then check out the tips below to stop your helmet visor from fogging.
How to Keep Motorcycle Visor from Fogging
If we were to rank these tips by order of effectiveness we'd rank a Pinlock visor as #1. A Pinlock visor pretty much eliminates fogging in all temperature extremes and you don't have to do anything other than install the visor. We know people who use it and they say it's that awesome.
The Pinlock system uses a silicon bead, which creates a double glazed window type of effect when the Pinlock visor insert is attached to the helmet visor. The pocket of air trapped in between the visor acts as an insulator for the inside temperatures in the motorcycle helmet. Blah, blah, blah, so what's the drawback? You do need a Pinlock prepared helmet. If this interests you, check out the available Pinlock inserts matched to helmet manufacturers.
Leave the spit trick to scuba divers and use treated cloths or an anti-fog solution that sprays quickly and easily on the surface of the visor to prevent fogging. Take it with you in your backpack or saddlebag to have every time you ride.
Open the Helmet Vents
Motorcycle helmets come with a number of intake and exhaust vents designed to bring outside air around your head to keep you cool. Some of those vents close which helps on cold mornings but it also restricts the flow of air and allows the heat and moisture inside the helmet to build up. Open these vents especially those around your face and mouth to keep the fresh air flowing.
Open the Helmet Visor
Fogging occurs when you have little to no airflow to clear out the moisture on the inside of the helmet. Most full face helmets and all modular helmets allow you to lift up the visor or shield which clears the air. An open face helmet has no shield, something to consider. But goggles can fog so use anti-fog solution. Some full face helmets also allow you to lock the visor in a slightly open position to prevent fogging.
Opening the visor helps with occasional fogging issues but not an ideal solution at high speeds and you might find it annoying to continually open and lose if the shield steams up routinely (some people produce more heat than others), and opening the visor leaves your eyes and face vulnerable to particles in the air.
Other Tips and Tricks
You have probably heard of some of the other, shall we say, eccentric tips and tricks to preventing the visor from fogging. We have no experience with RainX products, shaving cream, or rubbing a potato on the visor but apparently these suggestions work. Do with this information as you wish.
If you don't want to invest in the Pinlock or have a helmet that doesn't allow for the Pinlock, then stick with the anti-fog solution as a long term answer to any fogging issues. If you have continuous fogging problems despite trying the tips above you might want to look into a new helmet, preferably one that uses a Pinlock visor.