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As the respondent above suggests, checking the software date is a good first step. You've had a goodly amount of work done gratis by your local dealer, which my one-and-only would not think of. Hell they've told me straight "we don't work in bikes over 10 years old). Eff them, and all their offspring. Fortunately my bike has been pretty reliable although with the pandemic I'm not using it for a daily commuter... only go into the office 3x/week.

But... "they all do that" well at least many do, if you've dug into the forum here. Mine does, sometimes, but I've subconsciously learned to keep a light twist on the throttle when coming to a stop. This is effective almost all the time.

Suggestions....
1) Get your software date checked, update if/as your dealer will. Note, some dealers have been known to be less than truthful on occasion and the general trend here is suspicion. This is exacerbated by the near-complete dearth of technical material made available to owners and dealer techs alike Yes, dealer techs can be just as far in the dark as we are, which simply should not be. But you didn't come here to listen to how great these bikes are, did you? Be sure your bike has received all appropriate recalls, there were several.
2) Use 92 octane gas if you can get locally. I ran 89 octane with10% ethanol for the first four years of my ownership, and suffered the frequent hot stall thing. I use premium now, which still contains 10% corn juice, can't avoid that, and still have some very occasional stalling.
3) A GS-911 could log battery voltage in real time. Heat is the enemy of batteries, and the K1300 batt gets pretty warm. Some say to use the metal jacketed Odyssey battery. The do seem to last a long time, I just had mine load tested (plastic case) after five years and was told it was "Just fine". Data point: my bike didn't care if it was warmed up or not, it might stall.
4) There's an auxiliary wiring harness that puts more copper between the battery positive and starter relay, then to starter, the better to carry the amp load of starting. The purpose of this mod is to address the no-hot-restart condition, where after you've stalled, the bike won't crank, as if you battery is dead. You can make this mod yourself rather than buying from a dealer, there's a thread here somewhere that details it. You'll need handy skills and will have to strip the tupperware. Be sure to mark which screws go where.
5) K1200's had a recall for warped airboxes and the idle air control valve(?) in the bottom of the airbox would get gunked up and have to be cleaned. Not for the faint of heart to remove the airbox, I dunno your skills or determination level. Supposedly, K13's are not affected.
6) Make sure your throttle cables are appropriately snug (something I've been meaning to do). My theory is that loose cables may allow the throttle plate to wobble a bit when not strongly into acceleration/deceleration mode, giving varying signals to the ECU on a time frame the ECU can't smooth out. This is pure speculation on my part, but a bike 12 years old could likely do with some cable attention.
7) You can get your ECU's fuel map remapped/adjusted. User Botus here has little but scorn for expensive tweaking of adaptation values, but others have reported great things. Not inexpensive, and should be followed up with a dyno session attended by someone deeply skilled. I take no stance but to observe that if a full power air/fuel ratio arrives a little earlier in the rpm range, you'll feel more power at the probably expense of fuel economy. Some do, some don't. In taking no stance, I won't name those offering remapping, you can locate them without much work.
8) Then of course there's always aftermarket ECU's or piggyback units such as the Power Commander.
9) There are two gizmos that alter the ambient air temp sensor readings that are reported to the ECU. I got one and it made no difference. Still, better minds than mine infer that hot stalling is related to a too-lean condition, and the aforementioned gizmos are supposed to cure that. One of them, IIRC, is adjustable.
10) In days now gone by, R bike owners in particular removed the charcoal canister from the evaporative control system. This does not seem to be a frequent or popular mod with K44 bikes (K1200 and K1300).
11) Search this forum.
12) As you go forward, report back your successes and fails. The group has not generally resolved this yet, and need to. There's always the possibility you or your tech will find a nugget and beat a path to your door. Really.
 

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some further thorts...
1. Thinking that BMW will step up to the plate on bikes now some 16+ years old is futile. If they were ever going to, it would have been done by now. They have little to lose, and no upside when a few cranky old futs gripe about how their far-off-warranty machines work. I'm one of those.
2. If anyone is going to gripe about fuel quality, they're likely chasing a moving target. Fuel age? I've used 7-year old fuel from a resto project a friend did. He had a full tank sitting for SEVEN YEARS in his garage; I being the cheapskate that I am, could not let him simply dispose of it (what could he have done?). I ran some first in my lawnmower, without issues; then in my bike, again without issues. That seven years of storage was in average humidity of 70-plus percent.
3. Back in the 80s, BMW and other car makers ran into problems with fuel condensing in a gummy mess on the back and stems of intake valves. BMW tried a number of things and physical deposit removal via walnut shell blasting seemed to cure the issues - temporarily. It turned out that changing EPA regulations had altered the composition of fuel sold nationwide, leading to deposit issues. In response and after several years of poor consumer experiences, a new federal regulation required a certain minimum detergent additive level in fuels. BMW (and others, including Toyota) found the detergent level insufficient and formulated among themselves a new fuel standard, which came to be known as Top Tier, having FIVE TIMES the federally mandated detergent content. That seemed to solve the problems of the 80s. (That direct injection engines are now/again experiencing somewhat similar problems is a different matter I'll not go into). SOOOOOOO.... if you can, find out whether your local fuel supplier is giving you Top Tier gas. Here in Hawaii, it's all Top Tier, yet we (I) still have stalling issues. I've learned not to let the throttle go to rest at stops if the engine is past the high-idle warmup mode.
4. I got one of the O2 sensor signal manipulators that makes the ECU think it's 20 degrees colder, thus supposedly richening the mixture. As pointed out above, the ECU soon "learns" of this and the device has been of little use. The AX-FIED or whatever, which unit I don't have, may be better, it certainly should be for the greater cost.

Some say a little knowledge is a dangerous thing. There's "knowledge" floating about in reference to the hot stall issue, but no one seems to have reliably solved it, suggesting that either a) the problem has multiple causes and no one has correctly all of them, or b) some can sort the most pressing issue, leading to a subjectively better experience, but see a).
 

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Botus says the O2 sensor (air temp) tweak of the Booster Plug is negated in close loop operation by the O2 sensor and ECU. Mike claims the AX-FIED modifies the closed loop portion of the fuel map by manipulating the O2 sensor signal. THEY ARE SAYING THE SAME THING for different products and if so, they'd both be negated in low rpm closed loop operation by the O2 and ECU.

Modern EFI operates in closed loop mode (integrated control of A/F ratio with both O2 and fuel map in the ECU) up to some point, say 1/2 throttle, then (gradually) goes beyond stochiometric to a richer fuel/air ratio that yields the best power. This is done to meet increasingly stringent emissions standards, and get better miles per gallon in the most commonly used rpm range.

Aside from simple O2 sensor signal manipulation, one of the operational intents of aftermarket devices is to reduce the point at which the A/F goes rich for power, making the power arrive at a lower rpm range. "More power" = feels good. There are several ways to achieve this, 1) replacing short term fuel adaptations stored in the ECU (which Botus strongly disfavors), or actual ECU remapping which is the (more expensive) proper way to fix what BMW may have bungled. Assuming one's machine is in fully correct working order, something very few can know for certain.

So if my reading is correct, Mike's "I hope this helps explain it" absolutely does not explain "it". I welcome anyone with better reading comprehension of the above, or deeper knowledge of EFI functional concepts, to cut it and set me straight.

vonBlitz, you might as well install the Booster Plug, since you have it, and it'll take about a 1/2 day to put it in (my experience, YMMV). Then ride some and tell us how it goes. If you later install the AX-FIED unit, we'd all like to hear how that goes, in comparison. If Botus and Mike are both correct, each device will yield similar results.
 
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