I have an 83 venture and have had a wobble now and then , and it is after i get new tires. I have found that what you think is the frount end is all over the road but it is coming from the rear. So now when I get new tires the first thing I do is to snug the axle nuts on both front and back and snug the hell out of them and the wobble goes away.
Also snug up all the frame bolts, and as for tire psi check the tag on the frame for how much needs to be in the tires I think it is 32 psi front and 40 rear , but all bikes have a tag to tell you the right psi . I do this and the ride is just great:fireman: