valve adjustment, speed and mileage

[GZ250]

I use the Suzuki brand (10W-40) from the beginning and it seems to work ok and as i said i dont feel or think i have any clutch problem. The only time the gear does not engage fully if I do not pull the lever fully up and that happens if I wear different kind of shoe that i am not used to and that is just because of the thinkness of the shoe.

Now for the next oil change i am think of using the Rotella as i read a lot about that in this forum, so i will try that. do we get Rotella in (10W-40) ? havent checked that oil so i dont know much about that.

by the way when a clutch starts to show any signs of problem (slipping) what are the indications. For doing the valve adjustments myself, now i know where they are and how they look like, i will gather courage to do myself

Thanks.