i put a brand new carb on my sons 88 lt50 & plugged the oil tank & am now mixing my own oil & gas. put an inline filter on the gas line & i took the exhaust cap & silencer ( i guess thats what that bar inside the muffler was) off. It ran fine at 1st for about 20mins & then cuts off. let it set & it will start & do the same. can someone help. any info will b greatly appreciated. could it be the carb idle & airflow screw settings? if so whats the best way to set it. or the float? & how do i set that?....sorry for the long post, im new & am growing tired of working with this atv. please help. i just wanna get my 6yr old son riding it like it supposed to.

 

When it stalls check to see if it has spark. A lot of times stalling when hot is a sign of a weak coil, once it cools back down again it will run. If it has spark then you are probably chasing a fuel issue.

 

I agree.
If the problem persists, I'd clean the carb to make sure it's fine then I'd do a compression test.

 

its getting spark & good compression. carbs clean. so i cheked the petcock it was gunked up & cleaned it real good. the petcock has no off position only prime & on. when i unhook the fuel lines & have it in either posistion fuel flows freely from one line at all times.is this normal? is this because its a vaccum line? & does anyone kno the carb settings for the idle stop screw? i know the other is 2 1/2 turns out right?