Just try to relax, but still stay in control. The gyroscopic effect of the wheels on the busa will keep it going in a straight line. Rider input is what usually screws things up. Don't get me wrong, there is a fair amount of wind around the big rigs, but it should only take a slight pressure on the inside grip to counter it.
Pointers:
1. Try to stay to the far side of your lane, away from the rig, when passing. This keeps you from catching all the air being pushed around the front of the truck. It's usually only bad a few feet to the side of the truck, and your lane is typically about 10' wide. To see this in action, find a 2-lane road frequented by semi's. As you approach them going the opposite direction, allow a few to pass by while your near the centerline (NOT on it). Now for the next semi, move to the far side of your lane. You'll notice a BIG difference.
2. If you're following a semi, there really isn't a good place to be, but staying back a little bit and keeping his mirrors in your view will keep you out of the worse turbulence. The air being pushed around the front of the truck is trying to recombine behind the truck. Imagine what the smoke streams look like in wind tunnel testing.
If you just keep in mind how the air flows aound an object, you can predict where the turbulence is going to be the worse. Just minimze the time you sped in the rough areas.
Hope this helps you...Good Luck