pw80 will not stay on

[TONY8A]

pw80 full throttle dies

i tried to restart my sons pw80 a few months back,
the bike will start but will bog and die when you throttle. i took it to a shop and they told me what it was but i lost the invoice and for the life of me i can not remember except some thing about a main seal? i think! any ideas?it was running great before.
thanks for any help or ideas! :bang:

 

[zaneyzrex]

go thru carb. if its been sitting the main jet may be clogged