I have a Honda Racing hat that is useless since it blows off so easy. I end up wearing a baseball-style hat that has an elastic head-strap (instead of a pin or buckle adjuster). Fits just snug enough.

 

I turn the hat around for highway cruising. If I am going over the limit for spirited driving I take the hat off and put it in front of the seat so I can grab it easily when the speeds come back down.

 

Windows up and a Rick's aeroscreen is a must for 100+ driving.

Otherwise, have your passenger keep her/his hand on your head while you drive....essentially holding down your hat, hairpiece, and/or head.

 

I find a forward facing hat wants to come off ~ 60mph, while a rear facing hat wants to come off ~ 100mph. I also find that simply taking it off is easier than worrying about the occasional complicating crosswind.

 

My hat stays on fine, but I have to put some effort into it. Under my seat (where nobody will find them) I keep little velcro strips. I stick a strip to the front and back of my head, then front and back of the hat, then I velcro it to my forehead. THIS WORK!! TRY IT AND TAKE PICS PLEASE!!!

 

The trick is to get the wind to push down on the front of the cap as well as the brim. The cap will fly off if you let the wind get underneath the brim.

 

oh,oh,oh....got another idea. Wear the hat as normal...and then get one of those silk scarves that the women from the 50's used to wear. Take that scarf and tie the hat down to your head.

Here's another idea, get one of those hunter's flannel hats with the ear flaps. The ear flaps tie down under your chin and voila you have a hat with a brim that won't fly off while you drive.

 

Had the same problem in my 1999 Mazda Miata. More than once I've slapped my head because my hat shifted due to wind (didn't blow off, but it felt like it was going to). Looks real funny.

Wear a toque instead if you must wear a hat. Or if you have to wear a baseball cap, staple your ears to the hat.



(I wear a thin cotton toque if I must wear a hat, i.e. too much sun...but I look like a bit of a thug when I wear the toque with my sunglasses.)