Left my helmet sitting on the ground one night when I went in to dinner a few months ago and it rained, helmet was full when I came out from dinner...
Ever since it has smelled terrible. Is there any way of deodorizing it? Not a removable liner.

 

Try Febreeze. Mine smelled like dank old head sweat and that fixed it.

 

Your helmet is full of mold. You can bleach it, say 10% bleach to 90% water or try Hydrogen peroxide at the same mix. Febreeze will kill the smell for a while but you need to remove the source of the stench. Might be time for a new one dude.

If you do use bleach make sure to rinse the hell out of it and then let it sit and dry in the sun.

 

+1

I live in S. Florida, sweat in helmet and dumb enough to leave helmet in a dk garage. Need I say, it started to smell BAD.

Washed the foam inserts and used that Febreeze stuff. Did not work well after the 1st application so I gave it a 2nd application spraying heavily. Wiped it out and now, I am GOOD TO GO!

BuzzCap7

 

If the Fabreeze, or the bleach mixture doesn't work, there is one that works for pet urine smells....

One cup ( eight ounces) of hydrogen peroxide

One TEASPOON of baking soda

Two or three DROPS of dish washing liquid soap

Put the dish soap into the eight ounces of peroxide...

Put in the baking soda...

Stir gently until the baking soda totally dissolves...

Pour, or spray, the liquid into the helmet, completely saturating it.

Let it dry, then, if the baking soda leaves a white powdery residue (sometimes it does, sometimes it doesn't)...rinse the helmet out with clean water....let it dry thoroughly....

Good luck.

P.S. This mixture is best if used immediately, as oxygen is released by mixing the soda and peroxide, and it weakens drastically in about a day, so you really can't save it.

 

Throw it away or use it for a hanging planter.

Get a new one. $39.95 DOT

https://www.hdforums.com/forum/dyna-...le-helmet.html

Here-
http://www.leatherup.com/p/Outlaw-He...et/262770.html

 

Maybe you could try out in the sun all day, then the Febreeze for upholstry (in the spray bottle) as it is a little extra powerful.
Didn't see a dog anywhere around your helmet, did you?

 

Or a pissed off cager...

 

This... You don't want to rock a helmet that has mold. Self-explanatory.

 

Laying a helmet on the ground is never a good idea. My two mutts lift a leg on any thing that doesn't move.