bike sluggish when accellerating

[Briggers]

bike is sluggish when on quarter throttle , it is like having a restrictor on the bike. any one any ideas.
Brigger

 

[dirtdigger]

Gonna need more info. What bike? stock or not? How long has it done it? Any recent mods? Check all the tuneup items and check to see if you have some jets getting restricted in the carbs.