at what age can kids wear adult bike helmets?
I will be meeting a couple kids I've never met before for a short ride and need to have helmets ready for them. I will not be able to get their head circumferences before meeting them and buying helmets for them. The kids are 139 and 152 cm tall, so probably about 11 to 13 years old. Are they likely to be old enough to wear average adult bike helmets (size 58 cm +)?