right hand goes numb

I get a numb right hand as well, I dont think I grip too tightly but being short I am lent over with quite a lot of weight through my arms / wrists.

As mentioned, in the MTB world this is recognised, and Specialized make gloves with a pad on the siatic (sp) nerve. Its on the bottom corner of your palm, opposite to thumb side. Suprised motorbike gloves dont have the same.

I've never taken it apart, but to speculate. Could it be that the throttle side vibrates more as there is obviously the moving throttle in there, as opposed to the solid rubber grip on clutch side.