This write-up was contributed by TFauch, including all text and images
Tools needed for Gear Box Oil Change:
1) Oil Pan (mine is an old bread pan that came with the house)
2) Oil slide (made from a water bottle)
3) Ratchet Drive, two 3in. extensions or one 6 in. extension, and 6mm Hex bit socket (you can buy these tools individually from Sears)
4) Tutela ZC90 Transmission Oil
5) Clear squeeze bottle marked at 5 oz. ( I used the measuring cup from the kitchen and filled it with 5oz. of water then poured it into the squeeze bottle and marked the squeeze bottle then thoroughly dried the squeeze bottle )

Location of the drain plug
Looking from the exhaust side of the scoot thru the rear wheel between the 4 or 5 o'clock position on the wheel you will see the only hex key bolt That's your drain plug.

No need to remove the exhaust or rear wheel
Slide the oil slide thru the wheel from the exhaust side so it extends beyond the wheel and tire and into the drain pan. The top of the slide where the water bottle cap use to be will now be in your way to access the drain plug. No worry you can push it (bend it) down so you can access the drain bolt. The bottom of the slide will not move too much because it will hit the linkage for the rear brake. Now loosen the drain plug (counter clockwise) lefty loosey and let the drain plug take a ride down the oil slide into the oil pan. Let the oil drain. Some prefer to drain the oil while the engine is hot because the hot oil will drain faster. I prefer to drain the oil while the engine is cool because I don't want to play around a hot exhaust and because all the crap in the oil will be settled to the bottom by the drain plug.

You're almost done
After all the oil has drained. Remove the oil slide and reinstall the drain plug clockwise or righty tighty. Now fill your squeeze bottle with 5 oz. of transmission oil and locate the gear box oil fill/dipstick (that lonely 1 inch black plug to the rear of the engine in the picture below)

Per the Owner's manual
The rear hub oil content is 5 oz. with the motorscooter perfectly upright on its stand.
The rear hub oil checking shall be performed as follows:
1) Place the vehicle on its stand on a level surface.
2) Unscrew the dipstick, dry it with a clean rag and then rescrew it completely.
3) Unscrew the dipstick and check that the oil level reaches the MIN notch.
4) Rescrew the dipstick completely.
Oil type: Tutela ZC90 (SAE 80W/90 API GL3 specifications or higher)
Tim
⚠️ Last edited by TFauch on UTC; edited 7 times