Harley-Davidson stopped making 2-stroke models domestically in 1966 (the final model was the Bobcat) and the last imported 2-stroke Harley-Davidsons were made in 1978 by Aermacchi of Italy. No Harley-Davidson models manufactured since then require mixing oil with their gasoline.
20w50
20w50 oil in the motor
No, but find out the requirements for the motor. Most normal motor oils don't meet manufactures requirements for wear protection.
20w50
You can use the same oil that you use in your motor
All regular harley's take 20w50 motor oil, regular or synthetic is your choice.
Under the motor
Four quarts.
3.8 liters
amsoil 10w 30 the best money can buy
Same as Harley evo motor local Harley dealer has in stock.