About your fear of falling...

I first learned to lean into fast turns when I was a child on the back of a motorcycle. My natural instinct, of course, was to sit bolt upright. The person giving me a ride stopped immediately and explaned it this way to me: If you're sitting upright, your weight is actually forcing the bike closer to the ground, which actually makes it more likely the bike will "drop". As he showed me with his hands, there are two options (you've really got to use your imagination here):

With leaning:
./ ...<-person
/ .... <-bike

Without leaning:
. I .. <-person
-- ... <-bike

That got my attention enough to get me to always lean with the bike into a fast turn, whether the bike has a motor or not!