I'll never understand why Larry did things that way. Why install 4V the front wheel with floating rotors and then build a custom adapter for a 2-pot caliper when the 4-pot calipers with a 20mm master cylinder are light years better in the braking department?
All you have to do is ask. There are several reasons for using the 2 pot calipers and 20mm master cylinder. The braking power is more than adequate for both the K75 and K100/1100/1200's. I have not had any customer complaints regarding braking performance. The feel is progressive yet firm at the lever. On the 'Executive' I used the 13mm master and 305mm/2 pot caliper combination with no issues. The lever response is good. The 4 pot brakes are not really light years better. The 305mm/2 pot calipers and adapters are used because the K75S tune-able forks are used. The S fork is the only one that can accommodate dampening modification. Both legs are valved for compression and rebound making them extremely compliant without sacrificing ride quality or bottoming out. One of the most welcome characteristic is how little they dive compared to the standard Showa forks. On' Beauty' and 'The Beast' the wheelbase is the same as the 100/1100 RS, and with the 17" quick steering front wheel on Beauty the long wheelbase handling is fine. The lowered stance brings down the center of gravity, makes the bike feel less top heavy and allows it to handle very well, similar to the RS. Nothing grounds when leaning aggressively, but your feet will contact the tarmac a bit sooner than normal when you really push it over. The Beast on the other hand was designed for boulevard cruising but it was very stable in the Corkscrew at speed at Mazda Raceway with the 18" front wheel when I rode it there a few years ago with my wife as pillion making a movie of the ride!
The 1100 series upper and lower triple clamps are deeper and thicker, making the use of classic headlight ears less practical because they are considerably shorter than the span between the upper and lower trees. I have used the larger diameter tubes in the K75 triple trees by reaming the holes to primarily retain the ABS II more than for the 4 pot setup. Also, the aluminum fork bridge is not compatible with the 1100 series fork stanchions and the flat metal brace with plastic cover has to be used, another consideration regarding aesthetics.
That's my spin and I am sticking to it.