Up there, just eventually, for thoses who's been diving... another link to complete with Askamaskinservice
https://www.motorcyclespecs.co.za/model/suzu/suzuki_gsx1100ef 84.htm
Sure most already know this page, but for those who skipped reading the whole thing...
"......anti-dive brake systems, it creates new problems with suspension response. The trouble is that the system can't differentiate between fork movement that results from braking and fork movement caused by bumps, cornering loads, etc. The compression damping can be increased by any major movement of the fork. Unfortunately, you want normal,moderately damped fork response in some of these instances, especially when cornering hard through bumpy turns. With the GS1150, you sometimes get a suddenly stiffened front end that can't respond to bumps and that isn't giving 100 percent to keep the front wheel on the road. Combined with the 1150's mediocre tires, this can lead to sudden slides during fast cornering in a series of stutter bumps or through a gravity dip. Of course, if the bump is big enough and hit hard enough, the system's blow-off valve bypasses the anti-dive damping system. Part of the problem is the difficulty in predicting what will happen. With brake-activated systems, you can simply ease off the brake when you see a bump coming. But with Suzuki's Positive Damping Force (PDF) anti-dive system it is difficult to predict if the anti-dive will activate or whether a bump is big enough to trigger the blow-off feature and bypass the anti-dive. There is certainly little you can do to control it. Some riders found that shifting their weight as far forward as possible put enough pressure on the fork to activate the blow-off system, but the riding position was awkWard and other control problems arose. Varying the anti-dive's settings changes the point where the extra compression damping cuts in and can reduce the percentage of bumps that cause problems, but it doesn't eliminate the situation. Once you have had the front end suddenly stop responding to bumps in the middle of a corner and have felt the front tire skitter, your confidence in the machine is likely to drop sharply.
Fortunately, it should be possible to remedy the quirks of the front suspension or at least bypass the anti-dive system without too much effort. There are also plenty of good sporting tires available to fit the 1150. If we can hang on to our GS1150, we will try to remedy its only major problems and report our results in a month or so.
Looking past the anti-dive's pitfalls, you discover an excellent suspension system, which provides both comfort and control. Altering the fork's adjustments is simplified by eliminating the valve on the 1100 which changed fork air pressure. Rear damping and spring preload change with slick remote adjusting controls on the left side of the bike just below the seat. The rider can easily reach them while riding, and they offer a useful range of adjustments, allowing the bike to adapt to the racetrack and back to the freeway with just a few twists of the wrist. As a general standard, we used the No. 2 settings on the springs at both ends and on the rear shock damping, moving up to the No. 3 settings (sometimes with No. 4 shock-damping settings) for more aggressive passes down twisting roads. We used maximum preload to quicken steering a trifle or shift a bit more weight to the front in an attempt to overcome some of the anti-dive's glitches. Although the 1150 has less steering lock than the 1100, it is still pretty easy to maneuver at low speeds without a lot of dabbing or back strain.
Removing the anti-dive from the braking system has created a much more positive, solid feel in the brakes, which now use double-action calipers like the GS550's, and riveted rotors...."