Bike helmets will break. Reason being speed, hight, ect. I've always ridden with a helmet, a part from I've jumped on a few times bareback, similar to StormyBlues. My cousin has ridden with me in a bike helmet, although Chinga was very quite at the time, we were barely walking and he is only four. So it didn't really matter. A bike helmet was better then nothing at the time.