I like your thinking! Analytical and unafraid, the best kind. Yet, I suspect you may not have been exposed to some of our more incisive work in this arena.
Have a look at this machine. Compared to the standard motorcycle characteristics you describe, this one has a comparatively low CG, a very long wheelbase, and about 1/3 of its weight on the rear tire. Care to venture a guess as to its prowess in the 1/4 mile? 6.83 seconds @ 210 MPH, and on a relatively diminutive street-treaded tire.
Now, while I am stopping well short of a direct comparison between this machine and Slingshot, I am going to confidently offer that the same techniques and technology which empower this kind of capability will transfer directly to Slingshot. I'm just the man to do it