The first thing you should do is pretty obvious: open the vents. Getting rid of breath exhalations is what they're for.
De-fogging your shield is definitely a YMMV issue; what works for one may not work for you, so you should plan on trying a couple of these suggestions. But first, a word from Our Leader:
- I've tried a lot of things. Anti-fog inserts do work, but they create a halo effect at night around all lights, and they get scratched way too easily. I tried around 4 different breath guards, and the ones that come from the helmet companies don't work that well (if at all) in cold, wet weather, or in just very cold weather (32F and below). The only breather that worked 100% was the Respro (see below).
- Opening the faceshield is the cheapest and most worry-free solution, compared to anything else.
We've included some comments from our members. As was said before, your mileage may vary.
Breath deflector/breather/breath guard/breath box
Most helmets have an optional breath deflector that you can purchase. This is especially true if a model is made in both motorcycle and snowmobile versions. A breath guard concentrates your exhaled air and sends it out the vents more efficiently than when you just breath directly on your shield. New Enough and Extreme Supply are proven retailers.
- I live in a hot, humid area, and I used to ride with my shield cracked all the time. Since installing a breath guard I can ride with the shield in its correct (closed) position (except for having it up at stoplights). This makes my eyes less susceptible to drying out and also cuts down on noise and bug entry. Once you wear it a couple times you don't really notice it any more than you do your nose. My experience is only with hot, humid conditions. For cold weather, some members have said they work well, and others have said they don't work at all. You may have to spend the $15 to find out for yourself.
- I've used the Respro Foggy for the past two years, even in sub-zero temps, and haven't had any fogging at all!
- The improvement was evolutionary, as opposed to revolutionary. The chin velcro located it well in my KBC in terms of vertical placement (how high / low) but the velcro on the sides did not adhere to the liner. That made the seal less tight than I wanted, and still allowed some (though admittedly less) fogging. I pulled out the cheek pads and manually sewed in some velcro. Now the Respro feels tight on my face and seems like it seals much more securely.
- This one does work well, although there is a comfort issue involved, as it must touch the face to actually avoid any air coming out between your face and the breather. It also eats part of the available space at the front of the helmet. This wasn't an issue with HJC, but it was with Arai because it had less space between the face and the chin bar. It also leaves imprints on your face, even after a few minutes, so the face of a Respro user looks funny when s/he takes the helmet off. This might not be an issue to some, but may be to others.
This is a visor insert system that mounts via pins on your visor. This is only available in select helmet models and is totally dependent on whether your helmet manufacturer makes a replacement visor that is 'Pinlock-ready'. There is a DIY kit, but that appears to not be available in the US yet. Check Europe.
- I commute two hrs. each day. I cannot say enough good things about the Pinlock system. Since getting the Pinlock I have ridden in temps down to 22 F and in rain at 40 F, with my helmet shield and vents totally closed, and have experienced ZERO fog. I have tried everything that I can to make it fog up, but it just won't.
- I prefer a shield insert to a breath mask. My Fog City Shield insert helped with fogging on the visor, even in sub-freezing temps. I found that I got along really well with the insert. I found installing it was easy enough, but I did find the "halos" or starburst effects it gave around lights to be a bit disconcerting.
- Due to the aggressive adhesive, it's not that easy to get installed right without fingerprints (and you pretty much just get one shot). The extra layer of plastic to look through does somewhat compromise optical clarity. It also has some halo effect at night.
- I hated the Fog City insert when I had it. It is very hard to install it perfectly, and mine leaked after 3 big rain storms. And after it leaks... it is done; you can't reuse it/clean it anymore.
Some manufacturers are now producing anti-fog shields to go in some of their models. Check your manufacturer's website.
This is a substance that you rub on your visor like wax. There is a review on web Bike World.
- When I first started riding, some snow boarding buddies totally sold me on this stuff. I figured, "its only pocket change" anyway, so why not try it? The stuff went on okay, and buffed off enough to let me see without severe halos and starburst effects around lights. It took me about 5 minutes to be pretty disappointed, though. It helped a bit, but honestly, I don't think it did a really good job. I was riding along on a clear cold day, hit some fog, and had my visor INSTANTLY fog up so bad that vision went to zero.
If you want to go whole hog, go to the ADV Rider forum and see what people have to say about Schuberth helmets. They are generally regarded to have some great ATV helmets that are quite fog resistant. However, there are a couple problems. They aren't available in the US, so you have to order them from Europe, although some people have been able to find them in Canada. Since they're not sold in the US, they won't have the DOT approval on them, but they meet the much higher EU standards. Oh, and they aren't anywhere near cheap.