I recently switched the pedals on my road bike over to the SPD clipless system. The pedals I got have an adjustable spring. Tightening the spring increases the force required to twist one's foot out, while loosening it does the opposite.
Initially, I set the tightness as low as it would go. I have ridden the bike every day in the last week without issue, and without even the prophesied falling (though I'm sure my time will come!).
Today, while biking uphill against a strong headwind, my foot detached from the pedal, and I nearly lost control of the bike. It seems to me that this is the result of pedaling vigorously while also swaying a bit to keep my balance. This also seems like exactly the wrong time to have one's feet come loose.
This event makes me think I should tighten up the spring. At the same time, I have had several near falls where I forget to unclip at a light, but was able to quickly unclip after stopping and catch myself.
I have two questions:
1: Is it more dangerous to set the tension too high or too low?
2: What sorts of schedules might be optimal for gradually tightening up the tension while learning to use the clipless pedals?