Don't bother with worrying whether your state law requires helmets. The laws of physics require it. If you go down, you're likely going to hit your head. Don't ride without one. Too many riders have made that mistake.
On Saturday, I was riding with the Scouts to help them work on their Cycling merit badge. On our rides, these kids average about 10-12MPH, so you'd think it would be safe, right? One of the adults touched wheels with the Scout in front of her, and went down. Cracked helmet. Other than a scrape and some bar tape, she was fine. If she wasn't wearing a helmet, She could have had a serious injury.
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2020 Giant Defy 2
Fuji Cross Pro
Scattante 650-R trainer bike
'06 Kona Jake the Snake