90cc
a good size quad for an avrage sized 12 year old not a fat one is a 125cc for kids
i would get a 1cc since your probably a fail. lol
An ATV.
For a 13 year old it depends on your size and your experience with dirt bikes, but an 85 is usually the best size bike and fastest for a 13 year old. Unless you are really tall which you would need a 125.
110cc med size Try a 200cc Yamaha Blaster with a throttle limiter. After the rider becomes more experienced remove the limiter.
Yes You are allowed to race 2 year olds
old age .just a year is enough.
One size up from a ten year old boy. Or it can be one size down from a twelve year old.
They can't sign the rental agreement.
It must be a three year old.
prefferably the 85cc class