you can buy a bambino kart that you could use from the age of 5 you really need a cadet to race you have to be at least 8 for cadets but some tracks do allow younger ones on if they can prove they can drive safely,it also depends if the races are run to msa regs
my son is 9 and races a comer cadetin a local non msa sprint series, other cadet classes include honda cadets.
this is him and his school friends with his new kart a 2007 EKS with a comer w60 msa sealed engine




me acting as his race engineer and giving him some final advice before the final.......he came last lol




and this is a little off he had at his last race 2 weeks ago
little sod wasn't concentrating but did get striaght back on the gas!!




steve