On the other end of this spectrum I have a 120# 16 year old S2 driver with 50# of lead strapped to the kart. There would be another 10# had we ran S3. It’s tough as Chris is at one end and we’re at the other, but I’d hate to have my son pyle driven by a 275# kart. (Or any kart for that matter).
And I don’t disagree With Andy either, but being relatively new to karting I haven’t even heard of a time when the Senior class was 18+.