The thing with helmets is their plastic, you probably could blow dry it if you're careful not to melt any part of it. But there are adhesives and whatnot holding the various layers of shell, foam, and whatever else good stuff your brain bucket's comprised of. Heat from a hair dryer has potential to fuck all that up, but it can probably be done right if you really want to. I'd just let it hair dry, no biggie. Another thing besides just shrinking is the dryer could melt your gloves, so throw them in without the pucks and put a few towels in with it, just for protection