I am building a logo for a company building generators powered by bicycles. Target market is both personal and business-oriented.
Here are a few different iterations of I've come up with so far. Please pardon the color schemes (I know some of them are probably garish):
I tried to incorporate elements like a bike wheel and lightning bolt, but feel that the logo can be improved in terms of layout. The logo seems crowded and messy. Right now all the versions I've created appear rather juvenile (closer to something on a teenager's skateboard than a logo for a professional corporation).
How can I make this logo appear more professional?