I have the same problem. I also put phat bar tape on my bars which made a big difference. There is also Aztec Vibewrap that can be cut so you can customize it a little better to fit your bars and suggested by my LBS. I also put in line brakes on the top of my bars in addition to my STI levers and switch hand positions constantly as well as wear padded gloves. I still need to shake my hands out every so often too.