As has been said, it comes down to suspension. I love Zach and Ari, but they kinda downplay the importance suspension can have. Take a look at that GSXR. It has its ass sticking up in the air and forks sticking out of the triple tree more than stock. Basically, its geometry has been altered to be perfect for a tight, technical track.
Meanwhile, the V4 is setup stock for street riding so it is very plush. I am willing to bet if you spent maybe 500 bucks at most to slap proper springs in the front and a longer spring in the rear to raise it up a little bit, they would immediately get well over a second of lap time improvement.
