Under the bike, on the leading edge of the transmission pan, there is a 5/8" head bolt protruding from the aluminum pan with the head pointing forward. This is the engine oil drain. Right next to it there is a recessed 3/8" pipe plug with a internal hex. Don't touch this one.
If you want to drain the gearbox there is another 5/8" plug on the pan with the head pointing down hidden in a recess of the pan near the right side frame rail.
Both drainplugs look the same and have a small hex recess in the center of the 5/8" hex head and there are no other bolts on the bike that look like this.
Make sure the O ring on each plug is not cut before you put them back and do not overtighten the plugs. Ideally you would use a torque wrench set at the low end of the spec. These threads are easily damaged if you force them. Good idea to use a little teflon pipe sealant on the plugs when you put them back.
If you want to drain the gearbox there is another 5/8" plug on the pan with the head pointing down hidden in a recess of the pan near the right side frame rail.
Both drainplugs look the same and have a small hex recess in the center of the 5/8" hex head and there are no other bolts on the bike that look like this.
Make sure the O ring on each plug is not cut before you put them back and do not overtighten the plugs. Ideally you would use a torque wrench set at the low end of the spec. These threads are easily damaged if you force them. Good idea to use a little teflon pipe sealant on the plugs when you put them back.