I just can't imagine someone needing a $4000 bike for a first bike. And financing a $500 bike just doesn't seem reasonable. Don't take me wrong, you can use Credit Cards to your benefit, darn, I use my Credit Card almost exclusively, but I DO NOT buy anything I can't pay off by the end of the month.
If you do it wisely you can earn a lot of benefits with a CC, miles, points, etc. My first Plasma TV was earned by points from my AmEx. Credit Card companies don't like it when you pay your debt. Most credit card companies have a grace period where they do not bill you for any interest (usually for a month, now recently AmEx has a program where they don't charge you for 2 months). If you don't have a CC with a grace period, get rid of it.
But again, just paying $1 in interest is a waste of YOUR money. And usually financing for "toys" is not 5% or 10%, its usually 15%, 21% or more. Car companies usually have to give you 0% financing if they need to get rid of stock that doesn't move, like trucks right now, and usually that kind of financing is provided by the manufacturer themselves; "toys" on the other hand are usually financed through a third party, so no discounts.