This is a design issue on the i2. With the frame support going over the top of the x-axis, there is not a whole lot you can do about this other than switching to a different extruder. You may gain a bit on a direct-drive extruder but a bowden would give you more. I printed out the parts for an original printerbot on my i2 and then converted it. Was a fun exercise and gave me a few extra inches on the z-axis. Now I'm converting, yet again, to a more custom design that will give more frame stability.

If you look at the i3, you can see how they correct this problem. The support doesn't go over the top of the x-axis, it is behind it.