Funny you should mention oils…
When I had the XR I used synth oil, semi-synth oil, mineral oil…almst every oil at some point! But I changed it REALLY regularly, more often than not after every ride. When I pulled it down to put the 280 kit in it she was SO clean! I never adjusted the valves but did check them regularly.
Now with the Vor? She gets new crap oil after every ride. I dn’t think I’ve ever put expensive oil in it, I can’t justify the cost since it’s changed so frequently. That thing also is still very clean with excellent compression and stable valve clearances.
I’ll stick with cheap oil flshed through regularly.