Any suggestions for upgrading my brakes please?

[ProdigalGS]

The calipers were in better shape than I expected, but the screws and clips were heavily corroded. I now have new calipers and pads for just over £300, plus the cost of the easy bleeders. Having ridden the bike for a few miles now, my conclusions are:
Phase 1 - new EBC pads. These gave better initial bite but I was still unhappy with the progressiveness of the brakes.
Phase 2 - new calipers. Huge improvement, the rate of deceleration is now linear with the applied pressure, and it requires less pressure at the lever. Just what I wanted.

However...the brake lever feel is now firmer and the lever travel is reduced. I think I may have had some air in the system. This would account for the non-linear behaviour as the air bubbles start to compress under higher pressure. The bike was professionally serviced earlier this year and the mechanic replaced the fluid. I am wondering whether the job was done properly.

It may be that I could simply have replaced the pads and bled the brakes but I don't really mind. The bike is 9 years old and I was going to service the calipers anyway. The cost was modest and I'm now set up for the future.

 

[ProdigalGS]

Phase 3 - maybe I will fit 320mm calipers at a later date, but for now I'm just going to ride it for a while before I decide.

BTW removing the dowels is easy with a pair of molegrips. The dowel wall thickness is just 1mm so they are obviously just locating aids.

BTW 2 the OE calipers have different banjo bolts. The LH one is just a simple banjo bolt with a bleed nipple on top. The RH one is larger and more complex, with an additional piece in the middle. I was initially a bit nervous about fitting identical easy bleeders, in case the OE RH bolt served some special purpose. According to my research, the RH bolt is to enable automated brake bleeding at the factory and serves no purpose after that. You can see the difference in the photo.

 

[ProdigalGS]

Old calipers and fittings after 9 years and 20k miles. The pads are evenly worn, which suggests that the pistons were moving in unison.

 

[Leighwgold]

R1200/1250RT front discs , set of 7.5mm spacers for the calipers and uprated pads (did it on my 2015 GSA and it worked ) , or alternatively Galfer or Braking do a kit which includes larger discs, spacers and upgraded pads

https://calsport.co.uk/bmw-r-1200-gs-lc-13-18-2015/galfer-brakinggalfer-oversize-front-brake-kit-increase-to-320mm-includes-discs-sintered-pads-caliper-brackets/kg702wfs

Neil I like the idea of bigger disks but I’m curious as to how the calipers fit inside the spoked rims, the OEM Brembos on my 2017 GSA are pretty close to the spokes etc.?

 

[Neil W]

They are close but worked fine , if you are worried try just sticking a 7.5 mm spacer between the calipers and mount to see what the clearance is like. No need to change discs and as it is a static test a plastic spacer will suffice to confirm clearance

Neil I like the idea of bigger disks but I’m curious as to how the calipers fit inside the spoked rims, the OEM Brembos on my 2017 GSA are pretty close to the spokes etc.?