In my opinion not enough extension travel for your 6cyl bars at current ride height, as the front seems to hit the stops pretty hard. When the front tops out hard, the momentum of that pitch rotation causes the rear to dip which causes the 11psi slicks to bounce. The more pre-loaded the front springs/bars are when they top out, the more that topping out will upset the chassis. You don't want one of those little "jerk the tires off the ground" preload wheelies that upsets the chassis, you want a graceful wheelie that carries the front down the track.
Ideally, you want no pre-load of the front springs/bars at full extension. To reduce pre-load at full extension, your basic options are...
...slow front travel with shocks to the point that it doesn't top out.
...shorten/remove the rubber stops.
...increase extension travel by adjusting static ride height closer to the bump stops.
...stiffer springs/bars which will un-load with less travel.
Grant
