how realistic is this project for my bike

for the turn signals, I would have 5 LED's in a row. sequence them for the direction.

first thing that came to mind was a generator. used to have one on my bike when I was a kid.... alas, you probably have a power source.
http://www.woodengenerator.com/Related%20Sites.html

also, you may want to input wind speed.

tire revolution would offer ground speed, and you could total and log that for distance.