Sometimes. Mostly weather dependant. I have four...a carbon fiber half, an HJC 3/4, an HJC modular, and a retired Vega modular I haven't gotten around to chunking in the garbage yet (it still works, it's just not as comfy and user friendly as the HJC I replaced it with). I took the 3/4 with me on my 3k solo road trip...105 in Arizona to rain mixed with snow in Colorado, to an outright drenching in Kansas. A helmet certainly helps me with the elements. I wear glasses so the visor helps a lot. I've been caught in a storm with a helmet and without, and I prefer a helmet in the rain. I've also worn a cowboy hat in the rain...works really well as long as I stay where I don't have to go above 40.

Teek

 

I only wear one A) when its wicked cold out B) When i go threw a state the you have to.

 

I don't wear one here in town, But I do when I leave the city limits.

 

I wear one all the time. Went down making a left turn on some gravel in the intersection last spring, only doing 20 mph or so. I was amazed at how hard the side of my helmet smacked the pavement. It didn't knock me out, although I "saw stars".
Anyway it made me a believer, I think my head would have split open without the helmet. Just find one that's comfortable and wear it!

 

Nice Camel Werbeck! And Sportster to match! Very cool!