Speedfight 100cc cuts out on full throttle?

Lately my Speedfight has been cutting out on full throttle, Once it cuts out it starts back up fine. I've been having a look around google and seems like it could be a Jet problem/Mixture problem.

Does anyone have any guides on the right settings for the carb, Also anyone no what the standard jet size is? i currently have a sports exhaust on i've been told i should increase jet size by 10% is this correct?

 

What size was the standard jet?

 

I believe it is 84.