I'm looking for a way to make biking harder for me.
Why not just pedal harder? Well that's what I do now, and it just makes me hit more stoplights.
I live in a dense area and use biking during exercise breaks. I find it helps me to oxygenate the brain (yes I work from home)
I want the bike to do less with more effort without modifying it in a potentially harmful way. Any ideas?