well thats your problem...
Someone with a bit more knowledge may be able to confirm this but when i was sourcing mine from Japan i mentioned to them i wanted a sunroof. They told me that i might have problems with my height (i am only like 6"0 or 6"1) but that was my decider on not having the sunroof... True story
maybe if you take the glass out the top of your helmet will poke through