Just get that head covered. Helmets are a disposable item. One fall, one hit, one knock around and ya trash um. Spending allot of money on a helmet would probably cause you to keep a helmet that should be disposed of.
If you dont have a helmet then get one. A decent WarMart helmet can be had for 20 USD. Even in California.
I am not a mandatory helmet guy. But I am still around because I wear a helmet...
By the way, I have a big head and this one fits: Amazon: Bike Helmet, Basecamp Bicycle Helmet with Rear Light & Detachable Magnetic Goggles Lightweight Cycling Helmet
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