You could put it on the centerstand and measure how much air is under the rear tire. My 2008 has not been lowered, but it has nearly two inches under the rear tire. No wonder it's so hard to get up on the stand. The Ducati ST2 that I had before it didn't have enough room to stick a finger under the tire when on the centerstand - although I had raise the rear on that one about an inch.
__Scott R. Nelson, 2008 KTM 990 Adventure, 2001 Honda XR650L, Folsom, CA