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"In terms of Classical mechanics, one watt is the rate at which work is done when an object's velocity is held constant at one meter per second against constant opposing force of one newton."

Blah, blah, blah. What the hell is a newton anyway?

Just kidding. I'm a nerd. I know what all of this means. Basically, a watt is a way to express the rate at which work is being done. When you're dealing with electricity, volts x amperes = watts. I actually think that transposes to mechanics easier than the crazy jibberish above.

The weight you apply to the pedals is like Volts. The speed you're cranking on them is like amperes. The combined work being done can, in fact, be expressed in watts.

I mentioned this a few days ago: fixed gear doesn't seem to have slowed me down at all. When I first hopped on the Wabi Special, I gave myself twice the time to get to work, just in case. I figured that I'd have a hard time climbing hills. I also figured I'd have to take it slow going downhill. To me, this whole thing sounded like a recipe for a slower commute. I got to work as fast as usual. Maybe faster. I didn't have a cyclometer, but total elapsed time with stops was 25 minutes, which is par for the course. This has been puzzling me for a few days. I keep leaving a little early. I keep thinking maybe I'm just hammering it harder than usual to make up for the time. I keep getting to work in 25 minutes. The return trip home is also about the same. What's going on?

When I'm riding on my own, I tend to fall into this pace. It's not particularly fast, but it's not very slow, either. I always thought this had something to do with my pedaling cadence. I'd adjust my gearing to keep my cadence somewhat stable.

Riding fixed gear, though, I've found out that I have settled into roughly the same pace, even though my cadence is all over the place. I'm now starting to understand how this all works. It's not about cadence, it's about watts. Without being able to trade-off effort for crank revolutions with dozens of gearing combinations, I still exert roughly the same amount of energy per minute regardless which bike I'm on. I just push harder on the uphills than I normally would, and spin faster than usual on flat land. The same amount of energy exerted moves the bike roughly the same speed on average.

Bonus: the fixed-gear drivetrain is actually more efficient and feels more connected to the road. You'd have to try it to know what I mean. The end-result is a remarkably simple, efficient and fun way to get around, so long as you don't have many steep hills around.

Mystery solved.

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