AFAIK, BMW does not outsource engine parts for boxer engines....they pride themselves in producing these motors at the Motorrad plant in Berlin and have done since 1969. However, they do outsource things like sensors and many electronic components to Chinese companies, and have a manufacturing plant at the Brilliance Plant in Shenyang, China, mainly for the Chinese market, and at Loncin for smaller capacity parallel twins as well as in India for the 310cc motors. It's highly likely that all boxer motor main components are manufactured in Berlin.
Lets get some sense of balance...they are not alone for electrical faults...most European motor manufacturers have worse issues (Renault anyone?) and failing paint finishes are because they are hamstrung by barmy EU rulings on what they can or cannot use. The Japanese are not as hamstrung, and they are ahead of the game on electrical reliability and have a very different product ethic to the West....or did. Lately, there have been major failures in quality even on many Japanese engines, particularly Toyota/Lexus, where once revered models have been compromised by their CANBUS scandal (non-encrypted security) only recently patched with hardware and software upgrades at customer expense. They have also cheapened 5th gen Lexus model manufacture (eg no longer using the master craftsmen who used to undergo 12 year apprenticeships JUST to make the seats for the RX and LS models) and removing more reliable physical buttons for cheaper to manufacture touchscreens, as well as other cost cutting measures. It's why I stuck with a 4th gen model.
BMW, to stay competitive, and because of EU Construction and Use Regs, are forced to manufacture the way they do and are really no better or worse than many other brands. If you want the best reliability, buy a Japanese bike. If you want a boxer, buy a BMW. I put up with the ticking time bomb roulette, purely because in my own experience, they have been no less reliable than anything else I've owned despite the gloom and doom of forums. Think back to the 1970's and British death nell models, the cheap and utilitarian Jap commuters (which had plenty of issues), and the 1980/90's where only a handful of models were truly bomb proof. I had Yamaha engines stretch valves (FJ's and 750 Super Tens), Hondas with dodgy weak gearboxes and cracked cranks, but my first airhead motor was indestructible. I had Ducatis which only ran when in the mood to, which constantly suffered from crankcase oilseal failure (900SS Darmah), blown rectifiers (600SS) and swarf in oil filters. Guzzis which corroded in front of my eyes and blades which popped fork seals and went through head and wheel bearings, along with damp starting issues. Kwackers that suffered frozen carbs.
I know from my experiences with blood bikes that despite all the niggles, properly looked after, the 1250 boxer is a gem with regular servicing and will run to large mileages. We had some issues with the first TFT dash models and many 1200/1250's suffer from casing and wheel corrosion due to the paint systems forced on BMW. My own remedy has had to be brought to bear for my current RT, and that is protecting the paint, knowing of the crap protection water based systems offer by respraying wheels and parts of casings then using a protective clear coat. Mechanically, I've had many rattly beemers but have yet to have one which has suffered camshaft failures. It happens and it may be a lottery but compared with most modern cars (which are disposable crap) they seem no worse and have IME the potential for high mileages.
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