Well said doc0c.
naisme, the time to begin to influence and inspire your coworkers is after you get the job.
And don't cross-thread your bike commuting and your bike not-commuting-because-I-buggered-off. As a potential employer, unless I'm just looking for a seasonal or term employee, I want to know there's a chance you're going to be around for a while. So if I get the sense that you are a snowbird or prone to go off on walk-about, it will increase other reservations I may have about you. I can't think of any reason why your choice to commute by bike needs to come up (unless you're such a hot shot with multiple offers that you're seeking info on their support for your life choices so you can assess your decision as to where to work). But if your bike trip is a significant part of your back story, then have an answer to the question they're really thinking, which is how long are you going to be around.