After taking my gas tank off and putting it back on after a week or two, my bike is having a hard time starting. Sometimes it sounds like it's getting a deeper 'kick' when I hit the starter with half/full choke, other times it sounds like it's just the starter working hard. My spark plugs are only a month old, and they looked clean and to spec when I pulled them out. I also suspected that it was old fuel, since it sat for a week or two, so I drained the carbs as well.

My worry is that the evap canister on my e33 model might need some messing with. In this picture that's on my rear fender that I attached, it looks like there's a connection to the carbs. Do I need to remove this as well if I'm not using the system all together? Or is there something else that's causing it to not start up?

https://imgur.com/gallery/V2r9DMH

Is the battery in good condition?  Maybe put a multi meter on the battery while starting, it should not drop below 10.5V over a few seconds.

It may sound silly, but did you open the valve under the tank after installing it? I know i forgot to open mine once and was starching my head why the bike is not starting 

So I had just replaced the battery Weeks ago and it stays above that when trying to start, 12.6 when just sitting.
The fuel line seems fine, I even tested it by pulling the hoses off after closing it again, and there was gas in the lines.