Matt, I got my son involved in kart racing when he was 8. We purchased a used kart form the track owner for 1k and just started turning laps. That kart ended up winning us a state championship 2 years later. Where we raced it was all about the tires and that's where we won and lost races. When he was 15 we called it quits so he could play HS basketball. The time we spent together racing was AWESOME. He is 21 now and we are as close as ever. Kids don't remember what you buy them, they remember what you did with them. Enjoy your time together, you will have a blast
AL