[Mr Gazza]

Due an oil change on the ol' air cooled 900.
I usually choose an oil for a particular engine, and stick to it. I use Castrol Power1 Racing 10w-40 fully synth in the Monster... Always have done.

During my Alfa ownership I was lambasted by various enthusiasts about the virtues of Petronas lubricants, particularly Selinia 20K, which boasts the ability to perform properly for up to 20,000km and is rated (by Alfa people) as a far superior oil. They reckon nothing less will do in an Alfa.
This is in liquid cooled car engines of course. My Monster is a slightly different kettle of worms.
I have steered clear of "ordinary" car oils in the past, but the main reason for using a motorcycle specific oil (like the Castrol) is that they are suitable for wet clutches, which most car oils are certainly not!
But I have a dry clutch, so I don't need to worry about that aspect.
Just wondering about changing (permanently) to Selinia 20K 10w-40 semi synth... It's not that different in price to the Castrol.