need help
 

i just bought a go cart from my neighbor he says its a 150cc from tractor supply company. it wont start unless i put starting fluid into the carb then it runs until i let it idle then it just dies but if i rev it up it stays running. when ever i try to put it in drive it jerks backwards i cant seem to get it to drive forward. he said he took it apart because the reverse was broken. is there anyway he might of put it together backwards?