I have an '83 so they should be the same. Look towards the bottom of the engine on the right side between the peg and the brake. there should be a sight glass on the block with a small peg that has a slot in it sticking out of the middle of it. after cleaning the outside of the glass if you still can't see the level due to the glass being dirty on the inside, get a flat head screwdriver and turn the peg in the middle of the glass in a complete circle several times. This is a cleaner and should clarify the inside of the sight glass. now you should be able to view the oil level, but make sure you put it on the center stand first.
I use Motul 10w40. Good for the engine, clutch and stator. Check with your Honda dealer.
1984 to 1987 same engine same bike.
A reverse gear can be added to a 1985 Goldwing Aspencade. It is best to have it done at a specialty shop that works with older Goldwing's.
Look at the back of the engine where the clutch line goes in the engine. 3 bolts to take out and it's in your hand.
Oil drain plug is located at the back of the engine, right side, ( foot brake side ) towards the bottom of the engine.
How would you change the headlight bulb in a 1987 Honda goldwing? GL1200
about eleven quarts. Best to start with ten, then get engine to operating temp, and check level at idle and adjust.
I would read the owners manual
The first Honda Goldwing with fuel injection was the 1985 LTD model produced until 1987. When the Goldwing engine was enlarged to 1800cc in 2001 then that model and all susequent models had fuel injection.
This is a 1200. Did you check oil level in final drive? Differential. Could be in need of adjustment also. If the clutch does not slip, and you can shift ok up and down, might want to look elsewhere. Also might want to check the u-joint on the drive shaft.
engine light
the dipstick is near the back of the engine compartment. Check while at running temp