I use the ergon grips with short bar ends on an all rounder bar but I find the numbness comes from the pressure applied to my palms. If I try to sit more upright it relaxes that and circulation returns. I tried both positions of the bar (flat and on the ends like hoods of a drop bar and find it does it both ways) That is an issue alot of people have including myself and I haven't found much of a solution for it except to take my hand off the bars for a few seconds one at a time.