Ideally, parents should wait until their child is 1 year old before taking them for a ride on their bike via a kids bike seat. If you are excited and don’t want to wait that long, some users have taken their kids out as early as 9 months. If you are excited to get out there but are unsure if 9 months is too young, you can always consult your pediatrician to determine when is the best time for your child to get out there and hit the trails with you.