What is the cure for low speed wobble on a 1999 Vmax Handle bars shake when decellerating around 45 mph. and light pressure on grips.?

wow you have opened a whole can of worms here I own a 1995 vmax that had exact same prob . these bikes are notorious for for wobble you should read about the furbur fix there good and bad things about it I was going to perform this steering head adjustment on my bike but did not see the so called plastic washer in my service manual you are supposed to replace with a solid washer.any way if you read about steering head adjustment too tight could cause high speed wobble ,so low speed wobble suddenly dont sound so bad . anyway I started reading about suspension tuning trust me not as simple as you would think.I am not a pro motorcycle tech but have worked on many bikes even taken a few down to bare frame etc... some things are best left to a pro but dont let me discourage you it could be a simple fix like a front tire or like my bike I decided to put new handlebars on (dragbars) turns out the old ones were slightly bent have not noticed wobble since.BEST OF LUCK!! hope this points you in right direction close inspection could save you lots of time and $$$$