I kno its a dirt bike.. but my bro needs your help. He kick starts it and it runs for like 2-4 seconds.. gives it throttle and it dies out. It does this ALL THE TIME now for some reason.. do you know why and how to fix it?

 

make sure he is doesnt have the choke all the way out and make sure he is getting enought fuel to the carb. thats all i could thank of right now.