vibration help!

[JIBTEXHNKA]

yesterday i went for my longest ride so far (60 miles), and DAMN. at freeway speeds the GZ vibrates like something inappropriate for children. i had no problems staying with traffic, but the buzzing is just downright uncomfortable for any longer than about 15 minutes at a time.

i assume everyone experiences this to some degree, so what do you do about it? staying off the freeway is a good short-term solution but around here it's hard to avoid 55mph+ roads and still get anywhere in a reasonable amount of time.

should i eat more ice cream and get more butt-meat? wear padded jeans? get a seat cushion/aftermarket seat? just quit whining and deal with it? any suggestions would be great.

is this mostly because it's a single cylinder? or because it has to rev quite a bit to maintain 60+ because it's only 250cc? probably a mix of both, but i don't know.