66cc gas motor power problems.

I dont know if this is posting a form if so here is what I need so much help with. I have a 66cc 2 stroke gas motor and it runs great some times. when I'm out riding it it will go to full power and ride good at full power but after some times a mile or even less or some times rides good all day. but what happes is when it riding at full power it will all of a suddon lose power as if it is wanting to die but it dont I can let off the throtle and it will idle and I can rev it up and it sounds good and some times it will pick up power and then bog down again any idea I have done every time from check the spark pluge to check all gaskets and even looking and taking apart the carb to even takeing the motor apart . but have not found anything wrong I have a felling its the carb or even maby my carb but dont know for sure. again if any one can help I be so happy

thanks yea I have watch that video on youtube a few times and I have adjusted the small black clip a few times and I have adjusted the copper spring that the floats moves up and dow to allow full in to the bowl ect and I have to turn the valf off when I get home or it will leak the intire tank out and thats why I think I had a carb problem because it should not do that and I have looked at the bowl and didnt want to mess with it much but I will look in to that aera a little more thanks

hey I have fixed my motor bogging broblem it was the spark plug that cam with the kit it was fouling out like crazy so I bought Bosch Platinum at walmart item number 4302, it has two electrodes protruding from the spark plug for a much hotter spark and a path for a spark and talking about increased power and tork. this I belive today I got the trike up to at least 30 mph.....