1980 Suzuki RM60 - wierd engine problem

[acanz]

I have a 1980 Suzuki RM60 and it has a wierd engine problem. Sometimes when it starts or during riding at full throttle, it will bog down, lose power, and then die. Other times it will be fine. Any suggestions?

Heres a pic of me wheelieing (Im very proud of that because it was half an hour after my friend showed me how to do my first wheelie). My hair looks like a mullet, but thats because of the helmet. In real life I have long hair, not hillbilly hair.
http://www.zippyimages.com/38891.html

 

[acanz]

Fixed link.

 

[Gazza2005au]

#1: its an old bike
#2: look how u ride it
#3: your to big for an old 60cc (not being mean but your probably over the max weight limit for that bike)
my oppinoin it over heated