Is it ok to use Amsoil Synthetic 4 stroke oil in my 1984 Honda Big Red? Local farm store used to have regular 4 Stroke motorcycle 10-40 engine oil but now only has the Amsoil. Guess I am old school and a little worried about replacing regular oil with synthetic when it never has had synthetic used in it and it is 31 years old already and was built before synthetic oil was common.
Thanks