i use delo 400 in my XR, and in the gear box of my 2 stroke. no complaints so far
Delo-400 was my oil of choice too. Sorry to say that they just changed the formulation to meet either the new CI4+ or CH4+ specification (I forget which). They added friction modifier (moly?) and now no longer recommend it for use in wet clutch gearbox applications (your brp and my xr250r).
Shell rotella also reformulated to meet new spec but didn't add moly - so shell rotella and shell rotella synthetic are both still okay to use. Both are reasonably priced and available in gallon jugs at Walmart (at least most of the time).