Husaberg smoke
Husabergs will smoke if you have over filled the oil ,it should be filled to the bottom of the site glass not 1/2 way up.Take the seat off then remove the air filter & check in the rubber boot that connects the carb for a build up of oil. Clean it out if there is oil there.
There is a sponge filter in the Y rubber pipe that connects the top of the motor to the frame which also stops oil. May need to check this.