I am Anal with chains
The first chain on my XR was replaced under warranty as it rusted very badly despite my chain cleaning regime ( every 500 miles) and lubing after every ride. It was the side plates that were very bad. The chain that BMW use on these is no doubt cheapened down to the least ammount of money possible.
Having said all that the next chain was fine and i did not have to adjust it in 10K
So
Firstly if you are adjusting it regularly ( more than just between tyre changes) then it is possible that you are over doing it and possibly too tight ( my rule is that once they need adjusting more than between tyre changes they need changing)
Secondly the stock adjustment guides on the XR are, quite frankly, fucking useless so maybe invest in the HP version that are much more accurate and better looking.
They are quite a loose, by that i mean plenty of sag in the chain, so dont be fooled. The play i need in the Hypermotard is huge as an example and it looks way too slack when it isnt moving