The four-pot Brembo calipers fitted to the K1/K100 16v/K1100 look very much the same as those fitted to the early K1200RS/GT and some of the early 4v Boxers. They share the same pads and even the rebuild kits but the calipers are listed under different part numbers.

Does anyone know if the later applications can be fitted to the K1100 (for example)?

(Guess who's got a pair of very seized K1100 calipers) 

Well thats a bummer Mike the R1100 will most likely fit because the wheels and discs are interchangable but I am not 100% sure about the stud spacing. I have seen many BMWs that the calipers look the same except for the stud holes.
The R1150 are different to the R1100 and are more like the R1200

And I can say that the 1200 calipers don't fit, they come close but no cigar.

Rick,

That's pretty much what I thought. It must be the spacing between the caliper to fork leg mounts that vary.

That's what stops you putting the 4 pots on a 8V but you can do it by using the discs from the Mystik Boxers

R1100GS/R/RS/RT four-piston Brembo calipers for certain will fit directly to a K1100 with its 305mm discs. Any of that series of calipers using the single centre pin 'banana-shaped' brake pads (used through about 2002 when the EVO brakes arrived) work. EBC calls them FA407. Look closely at my K100RS 8V and you'll see them there, albeit, with 8mm aluminium offsetting spacers and larger diameter Suzuki discs.

It's the difference between the diameter of the discs and the offset. The bolt spacing of the fork leg where the calipers mount is the same for all earlier K Bikes, Oilheads, & etc.

A note of caution for anyone diving in there too fast: using a 20mm master cylinder works best if 'upgrading' to the four piston calipers from the two piston calipers of the earlier bikes, despite the 12 & 13mm (actually 13mm or 15mm) master cylinder diameters of the R100 Mystik or R100R...

Didn't the Mystik have an 18mm master cylinder?

Two Wheels Better wrote:R1100GS/R/RS/RT four-piston Brembo calipers for certain will fit directly to a K1100 

 
That's good enough for me. 

Thanks very much for the help. 

RicK G wrote:Didn't the Mystik have an 18mm master cylinder?

Mystiks had a 13mm m/c if single caliper, 15mm if double.