Ok so I got a mini bike today, the guy said it sat for about a year or more. I got it to run but if I let go of the starter or the left brake(saftey switch) the bike will die. I never changed the gas so Its possible the 2 stroke oil settled at the bottom of the tank and carb. it ran also whne I gave it throotle it bogged down and when running the battery drained and died. where should I start.

I would drain the fuel and refill with a fresh mix, replace the spark plug, and put the battery on a charger (or replace it if needed) and go from there. 

I am charging the battery now and am going to have it on a float charger over night ill do the gas and plug tomarrow, thanks.

if you have a bottle of seafoam layin around throw some in the mix.   2 stroke gas really gums up in carbs.