i got a service manual for my 883 today and was lookin at the oil specs. it says if you cant find harley oil to use an oil certified for diesel engines if you need to add oil. is it acceptable to use diesel oil all the time or is it an emergency type thing? i live too far away from a harley shop and dont reallt wanna pay $12 a quart for oil. what is a good alternative to the harley oil that want kill my wallet?