I have the '07 Bayou, tough little machine.
I think the capacity is labeled on the filler cap, but not sure.

Cartridge filters can be bought on eBay for cheap. Change your rear differential while your at it, standard lube 200 ml.
The owners manual shows you how to adjust the clutch. It's on the right side, two bolts hold the cover, loosen locknut, tighten adjustment screw until it stops, loosen adjustment until it stops, tighted locknut, replace cover and then you do the hokey pokey.
Ride Hard and Enjoy!