my memory fails me now,... but somewhere i read that(think ai) that this is a common problem and it usually has to do with the steering head. take apart, check for wear and or galding on race, clean and regrease the steering head bearings(repack), re-install and tighten untill you feel a click and then back off a quarter turn and your clunk should go away.
wait.... I remember where i read it!!!it was in the hog helpline section of AI awhile back so read your past issues!!!guy had the same problem as you. Article also told you how to diagnos problem as well
By the way, i have a 1996 wg.
wideglidebill.