I first noticed the problem when I was riding long distances on 10 speed bikes when I was about 20 years old. Mine go numb on dirt bikes, street bikes and bicycles. In fact, I sold the only street bike I ever owned because I just couldn't ride it more than 45 minutes. I wake up a lot with numb hands too or if I'm positioned wrong on long drive. Sometimes its the CT nerve (thumb and first two fingers), sometimes the ulnar nerve (last two fingers) and sometimes both. Mine stems from neck and shoulder positioning, not the CT tunnel. Rolling my neck, rolling my shoulders and shaking my hands alleviate the problems for a while, but I mainly just live with it even though it can be pretty painful sometimes. I think mine is somewhat hereditary because my dad would have this problem when he was flying stunt biplanes when he was my age (mid 40s now). I do think that learning to ride relaxed does help quite a bit. Or (and this makes no sense to me) when I am really, really fighting a trail for a long period of time, I don't notice the problem at all. I'm wondering if all the body movement I'm making somehow stops the pressure from building up on the nerves. Now my right forearm may start hurting, but I have never noticed my hands when I'm fighting every inch of the track. Weird.