#3 - I love the simplicity of your design and the way you broke the name up using colors. What would really sell me on this design is if the chain ring looks a little more like the other designs.
Entry #15 - I like this design too. As you are heading in a different direction. My suggestion is to make the name two colors like your other design and then may use the name in a horizontal fashion where the "CS" is currently located making it look like the pedal arm. Nice beginning on both designs!