This has been happening off and on. Last Sat, I went for a 30 miler with a 2 mile climb at 10-14% grade**. Lots of push/pulling. About half way through, my right hand goes partially numb. Pinky and ring finger, and half of the palm. I am (of course) standing, so most of the weight is on my feet. I've had numb hands before, but it's usually when riding seated for a long period of time.

My handlebars are bullhorn style that gives me a good grip for steep climbs. I guess I am a little confused why my hands are going numb when climbing. Any insight would be appreciated.

** EDIT: Here is the climb. Parts are 10-14%, not the entire thing. http://app.strava.com/segments/629980