Mineral oil in the clutch
 

I know a lot of the KTM guys just use ATF (with a flush) for the oil in their clutch system and I assume this would work for a GG? Mine seemed to loose some of its distance and I figured it got a bubble or just needs flushed. Will that work?

Seal and O-ring materials are different. Look at the Master Cylinder
cover to determine what you should use. Do not deviate or it will
stop working right.

Older bikes with the black cover used DOT 3/4, newer bikes with green cover mineral oil. Its also molded into the cover. I use Cam II hydraulic jack oil because I have a qt on the shelf, but almost any light petroleum base fluid will be OK, like ATF or fork oil.

I guess I should have made it clear that mine calls for mineral oil, I'll try ATF in it

I have used 2.5 weight shock oil in my KTMs for years and never had an issue. The 2.5 oil worked better in the cold and seemed to stay consistent. I have not done anything to my 2011 GG yet. Still giggling at just riding it.

Baby oil works good. It is mineral oil.