This is not a "how to reduce vibration thread" All motorcycles with powerful engines will cause numb fingers and hands on many riders of all ages. For me, the best solution is keeping your wrists strait with a relaxed grip. Also, when I am not riding aggressively . . . (Cruising, touring, site seeing etc) I have to rest my fingers on my brake and clutch levers to keep my hands relaxed. Many times, I will use a thumbless grip like bench pressing.