Puttin' my fat arse uphill
 

Ok ok I know we are talking a 250cc and yes I'm about 200lbs and I have terrible luck going up hill. Now we are not talking Everest here I'm talking low grade inclines in PA. Now I have much trouble pushing 60mph which for the riding I do is generally too fast. But seemingly any type of incline I can't push anywhere near there usually tops out at around 40mph. I dumped some gumout in the tank, letting that run it's course, I know the carbs probably need loved up a lot. Anyways my question is how my trouble am I experiencing 'cause of my fat ass, and any other tips, tricks, guides to make life on the commute a bit easier?

Down shift a gear and wind it out.
The GZ will not pull an incline in high gear.

my was the same until I mod the carb an filter

The GZ has a problem with any slight incline in 5th gear. Drop it a gear and pray a bit. Also be aware that a small headwind and an incline will always have you wishing for a bigger bike. 2 or 3 more horsepower would be just right but would compromise the reliability of the engine in time.
You can do the carb mods as suggested but don't think the bike will become a rocket sled. It may be just enough of an edge to keep you happy though.

It's the gear ratios. The jump between 4th and 5th is so large it makes 5th gear virtually an overdrive. It's great for the highway, as it expands the powerband just enough for elevated cruising speeds - but not awesome if you live somewhere that isn't flat.

As mentioned, use 4th and don't be scared of making your engine loud.

I second (third, fourth etc.) that, you can easily get up to 60 mph in 4th gear and not worry about doing any harm to your engine.