My 05 lowrider does the same. Was a little concerned when I first got it til my buddy said its normal

 

Yes, shift, don't kick.

John

 

There are no synchros in a Sporty gearbox like you would find in an automotive trans. Your shifts are naturally going to be inconsistant, depends if the dogs are lined up at the moment you kick it... and kick it you should. If you pussyfoot you risk damaging the dogs from a partial shift. The only time I ever mis-shift is if I'm lolli-gagging about in town and not give the pedal a positive input. That usually wakes me from my coma with an embarrasingly loud racket coming from the gearbox for a few seconds.

Another factor is the fluid you use, you want some consistancy hot or cold? Use ATF. Any other fluid will make shifting noticeably change as the box warms up and the oil thins out and the clutch drags less and the gears slide easier.