The software updates by ISTA is no different than a general update that is in who really knows how many modifications BMW makes per release.
The real issue with the recall change over that BMWAG was pushing is "how many recall bikes were done". Then the "how will techs know the recall was done" .. You can buy Nissin Calipers off ebay and install them yourself. When you visit the dealer they see hardware, but was that BMW recall hardware or ebay hardware?
So those answers are met with the ISTA update per Hayes caliper swap out. BMWAG knows the bike is done via ISTA on the backend. The tech knows that the recall is done on a bike with the new VO / FA code KK67. Only recall bikes get the new KK67 added to the VO / FA.
The ABS pressure sensors are a calibration inside the ABS module. Those sensors provide the data back to the KOMBI ( TFT Cluster ) for the brake pressure meter on the Sport Screen.
It was hilarious to me that when I got my K67 June 6th 2019, the first thing I noticed on the Sport Screen was the brake pressure meter reading. I could just go to the street corner and apply enough brake pressure to max out the meter from a mere 40 MPH. Of course that was completely wrong and it was one of the first indications that software was purely responsible for calibration on that reading off the pressure sensors in the ABS pump. It was not even hardly 30 days and there was a ISTA release to start helping this reading. The first release was better, but it was still wrong. The next release in September 2019 resolved the meter reading issue. Pure software calibration issue. No hardware changed, no fluid changed, just the calibration on the pressure sensors.
So the master cylinder delivers the fluid to the ABS pump. From the pump it is routed to the calipers. All there is in this system is volume and pressure. 19 Ratio is the typical magic number that most look at for volume in how much is moved at each squeeze of the brake lever. That movement of fluid is both directions. When you apply the pressure to the pump and calipers, the fluid leaves the reservoir. When you release the level the fluid returns to the reservoir. There is always this exchange back and forth of fluid movement. So the pressure is all about your finger or foot. Those are your response to how fast do you want to slow down. Squeeze hard, slow down, squeeze hardly, slow down more. That is the pressure in the system pushing on the caliper pucks. Volume is always the same until you start to change the lever ratios or master cylinder size, or caliper pucks size. Then there is alot of math that can say where you are in the volume vs pressure. The Ducati forums beat this issue to death out there. Lots of threads on volume and pressure with those guys to get to StarBucks safely.
Can you update the SW/FW in the 2020 M bike to the gps lap timer that comes in the M 1000RR? I searched on that topic and did not find a definitive answer. Any thoughts? I have not been able to find the wiring data yet on the M1000RR. I need to see how the new GPS lap timer will interface to...