After a 3 hour wait on the top of the Long Mynd, BMW assist arrived , diagnosed battery fault showing 3.3 volt jump started okay, returning bike to Rybrook for their diagnosis and decision
Had exactly the same on my 6 month old 1250 GSA last month, 12.4 v showing but same symptoms even though used regularly. Assist arrived, ordered and fitted a new battery the next day and has run fine since. Duff batteries seem to be common on late models????????And the answer is - 'Battery Knackered'.
Glad you got home OK Bob.