Antifog Insert for the DF Hood Visor

This is not my original idea. I came across this somewhere on the German Velomobile forum. It sounded easy enough to do so I thought I’d give it a go. The idea is to add another layer of Lexan to the interior side of the visor, leaving an air gap between it and the visor. This layer (or insert) becomes the interior surface. The air gap prevents the cold temperatures from transferring to the insert so condensation (fog) is less likely to form. This is the same idea as employed by the Pinlock system used on motorcycle helmet visors.

Here’s what I came up with…

Materials needed:


  • Design a pattern for the antifog insert that’s smaller than the visor opening in the hood.
  • Trace the pattern on to the Lexan sheet’s protective film.
  • Using some large scissors, cut out the pattern.
  • Remove the protective film from one side of the insert. This will be the side facing the factory visor.
  • Apply the double sided tape to this exposed side of the insert near the edge. Leave the red backing film on the double sided tape. Use a razor to remove any excess tape that goes beyond the edge of the insert. Be careful not to introduce any smudges or fingerprints to the tape or to the exposed side of the insert.

Antifog insert with double sided tape with red protective film still in place.

  • Remove the visor from the hood and clean it with something like Plexus.
  • Remove the red backing film from the tape. Position the insert carefully over the inside surface of the factory visor without letting the tape touch the visor yet.
  • Once you’re happy with the position of the insert, start at the centers of the upper and lower edges of the insert to press the taped edges to the visor, working towards the sides of the insert. You want the insert to follow the curve of the visor leaving an air gap between the insert and visor.

Insert installed with protective film removed.

  • Remove the remaining protective film from the non-taped side of the insert.
  • Reinstall the visor on the hood. That’s it.

The antifog insert has worked surprisingly well during a couple of early morning rides.