86 Trike?? No PICS???LOL!!! I've used Castrol 20/50 for a lot of years and never a oil related problem. Pick a good oil (there are a bunch) and change it as you should!! Don't like what you are putting it in?? Don't change it you won't have it long!!!
THE MOST IMPORTANT THING.......CHANGE IT!!! CHANGE IT AS YOU SHOULD!!