Recently on a couple of long runs the palm at the bottom left corner of my right hand gets very sore, so much that i have to put some sort of padding in the glove to dull it a little. It seems to be the right hand only and the happens on any of the 3 bikes that i use. I've tried riding with or without gloves and it seems to make no difference, still get the dull pain, can't work out why it's the right hand only.