R1200GS Adv motor cutting out (2008 MK II)

My 08 gs started doing this last October , at the time it had the decat headers and Beowulf end can fitted.
It carried on doing it all throughout the winter on the occasional cold run outs .
In march I decided because she's a keeper I'd take a trip over to see Geoff at hilltop and get a remap and hoped that it might sort this little niggle out as well .
Although it was a great improvement to my bike it didn't sort the stalling problem out completely it still did it but much less frequently . But since the weather has got warmer maybe the last 2 mths it hasn't done it once and I've done maybe 3k since April .
One thing I did check was my clutch switch as when it did stall it was a neutral only start ,just make sure you can hear the switch clicking at half lever pull.
Hope this helps someone ...gav

Well, my 2009 GSA has being doing this for a while now. Cut out a couple of times when out on a 50 mile run .. Scary stuff when you have a 38 tonne Scania breathing down your neck on a main trunk road .. he just managed to avoid me with little room to spare!!
This combined with what seams to be never ending leaking oil seals is just making me wish I'd never bought the thing. Although it is a fantastic bike to ride when it actually works, I just don't trust it anymore, not even to the bottom of the street and back, hence its been sitting in the garage unused for the last few months.
The GSA has always been my dream bike and I bought it in order to do some touring with the other half sat on the back, but I won't even take her out on it now in case something goes wrong and she gets hurt when the bike inevitably stalls in the most dangerous moment.
Sadly my dream bike has turned into a living nightmare!
I'll probably keep it locked up over the winter now and change it for a Honda or Yamaha next spring .. which is a real pity because nothing else looks like or rides like the GSA, but I need something I feel safe riding and something that I can trust.

My 09 used to stall. Hasn't done it since the Hilltop remap.

My 08 GSA stalled randomly with seemingly no pattern until I replaced both primary ignition coils.
The old black painted coils are crummy at best. If you are lucky the O2 sensors will survive.
Primary coil problems will be worse with a hot engine. Secondaries are unlikely to cause a stall because they spark after the primary coils.
Running decat headers, free flow can and free flow air filter will upset the standard ECU map increasing the stall risk and certainly risking exhaust valve damage. Info from Geoff at Hilltop.
I bought a Power Commander V from another Tosser. The map is close enough for my needs. The bike hardly ever stalls but does sometimes do a cough backfire.
The other possible cause is the the crank position sensor especially if it's worse with hot engine. The Hall effect transistor can break down enough to be ok cold but fail when hot. The ECU won't log a fault.

Suffering the same problem, the last two days my '09 GS (32,000mls) has been cutting out when filtering and changing down 3-2 when its warm, nightmare !
So my question, what do I try first, I'm thinking lambda sensors first, Motorworks have used for £45, or new for £90, I know which I'd rather do, but would I be throwing money away with the used ones ?

Coils first. Swap left/right as see if the cool exhaust swaps side. Sooty O2 sensor can be a symptom of Miss firing coil(s).