You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
When I rule the world, anyone making a hat or cap and claiming "one size fits all" will be the first to be marched into the ministry of painful re-education, (Moto: You will learn or die trying)
It should be so simple, I want a couple of peaked caps to fit under my helmet for winter riding, 1 waterproof in a normal cycling cap style, 1 warmish but not bulky that covers the ears and doesn't ride up in use (probably made of roubaix). They make them for pinheads, but not it seems for slightly larger than average people, I have tried loads over the years but all range from either "too tight to wear for long" to "you are ****ing kidding me you bastards". It's not like I am a giant, children don't point and gasp when I walk down the street, so why can't cycle clothing manufactures make a winter cap for a person that wears a l/xl helmet?
Just use a buff.
Buff - you can get warm merino one's too
I have tried buffs, they are a crap solution, they are not peaked, they are not waterproof and merino is useless when wet (with either rain or sweat).
No idea but I love the Mekons
Rapha do two sizes. The bigger of the two are ok if not massive.
Possibly Galibier. They make a cotton cap in a larger size, which I use and is a better fit than most One Size options.
The Rab Filament beanies are worth a look - it’s that slightly bobbly textured fleece material and is very stretchy - wicks really well too.
What about a cover instead of internal, where the lcy wind still blows through the vents ?
I picked up a very nice goretex lid cover, and while it does give the appearance of an eggcup, it does its job when that icy wind blows and the freezing rain is bucketing down
I have a Galibier waterproof cycling cap which is the biggest I've owned. Fairly normal sized head, but feels big/loose

I have the same problem. I had a Gore C5 windstopper winter hat for the ears and waterproof. And a Castelli defesa 2 for cool weather. That is really breathable and pretty waterproof.
Both worked very well, but I decided I could stand the look of them (vain yes).
I'm now using buff thin and polar hats (not the tubes). No peak but way happier with them.
Just remember #neverdoublepeak