1982 Honda CB450T-Hawk Oil Question

From what I remember in my automotive and aircraft schooling, using synthetic oil on older vehicles before the advent of new seals (about 15 years ago) will cause leaks because the chemicals in the synthetic oil will attack the molecular structure of the old natural rubber and break it down. So unless you have updated the seals with the new rubber, if Honda or aftermarket even does that, you are going to run into problems, in my opinion.