From Honda Trail Bike Wiki
A steamed up visor is caused by moisture (normally from your breath) condensing on a cold visor, in the same way as a kitchen windows steam up when cooking.
[edit] Prevention
There are a number of ways to prevent steaming:
- Fog City visor insert - introduces a small air gap, like double glazing.
- Pinlock visor insert - as per Fog City.
- Rub washing up liquid on the inside of your visor.
- Use a Oxford Huff Breath protector - a facelet that covers the nose and mouth, preventing breath getting to the visor.
- Bob Heath Visor Spray
Whilst preventative measures help, they don't always work, and so if you're faced with a visor that's beginning to mist up, try the following:
- Use your helmet ventilation system to push air up the inside of your visor.
- Open your visor very slightly (about 5mm).
- Breath through your mouth, over the top of your bottom lip; directing the moisture away from your visor
[edit] Additional problems
Steaming up on the inside is quite hazardous, add to the rain on the outside of your visor and visibility can be hideously reduced. Products such as Rain-X can help to make the visor slippery so that rain beads quickly, and slide off the visor.
