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Old 09-01-10 | 10:28 AM
  #6023  
puppypilgrim
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Joined: May 2007
Posts: 793
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From: Vancouver, Canada

Bikes: Brodie Force w/ Xtracycle, Dahon Helios, Merida Folding, Pacific Carryme, Softride Classic



So its 20 km door-to-door and usually takes me 51 mins. 29 seconds which is an average of 23.3 km/h (the long uphill from Kent Ave. to Kind Edward Ave in Vancouver is a killer). Last night after I put my daughter to sleep, I switched my bicycle gear from 66 gear inches to 62 gear inches (yes, its a singlespeed freewheeling bike). This lowers the gear and makes it slightly easier to climb uphill although speed on the flats is reduced. This has the effect of increasing my cadence.

I woke up early this morning before the alarm rang and had 2 tablespoons of peanut butter and 2 pears with a cup of coffee for breakfast before heading out. The higher cadence meant my legs felt "light" most of the time. Climbing inclines, I did not feel as if I was going as fast as before because I did not feel as much resistance.

Contrary to my expectations with a lower gear, it took me 49 minutes 15 seconds door-to-door this morning which amounts to a reduction of 133 seconds (2 minutes 13 seconds) or an improvement of 4.3%. This is a fairly notable gain.

For my commute with includes a fairly long portion uphill, I am 4.3% faster spinning a lower gear of 62 inches and averaged 24.4 km/h (roughly 1.1 km/h faster average). I don't know how much of this to attribute to the fairing. A fairing generally helps one of several ways:

- maintain a given speed with less effort
- achieve a higher speed with the same effort
- increase rider comfort

Since I don't have multiple gears, I am unable to go faster on the flats to raise my average speed on the flats than what I can spin with 62. The gains must be coming from the uphills portions of the ride. I also note that 62 gear inches allows me to accelerate more rapidly from traffic lights and reach my cruising cadence sooner. 100 rpm equals 18.4 mph (29.6 km/h).

So there you have it. Lowering a gear and spinning yields a faster time than mashing - even with a fairing. Its also less stress for your connective tissues. Of course, one individual's experience does not a principle make. Your mileage may vary.

To top it off, when I got downtown my local cycling coalition was out with coffee and advocacy surveys. So I stopped and did my part.
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