06-22-2015, 02:38 AM
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#1 (permalink)
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Cyborg ECU
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Aerodynamics of real-world bicycles
Researching fairings for my electric bike, I ran into this article and learned that fairings might be worse than useless. Who knew? Also, the tuck is the best. That's free! I can do more of that!
https://janheine.wordpress.com/2012/...orld-bicycles/
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See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
Last edited by California98Civic; 06-22-2015 at 05:49 PM..
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06-22-2015, 11:31 AM
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#2 (permalink)
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Master EcoModder
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Awesome! I'm going to go home and lower my stem tonight.
Who knows what they used for "fairings" though?
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06-22-2015, 12:55 PM
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#3 (permalink)
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Master EcoModder
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Good article, but I'm going to treat this like any other topic focused on competition.
I ride my bike for exercise, extra drag means more work, means a better work out.
Just like swimming, I've just started swimming this summer and my bathing suit acts like a parachute compared to the speedos the other guys are wearing. More work (more drag) means I'll be stronger.
In boxing the training gloves weigh more than the fight day gloves for a reason.
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You cannot sell aerodynamics in a can............
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06-22-2015, 12:59 PM
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#4 (permalink)
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Cyborg ECU
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Quote:
Originally Posted by Sven7
Awesome! I'm going to go home and lower my stem tonight.
Who knows what they used for "fairings" though?
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I think I'll place an interlibrary loan request for the article. I'll post what I learn into this thread. I plan to lower my stem, shave the ends of my MTB style handlebars so my hands-distance matches my shoulders-distance, wear non-loose ( but not tight) clothes, and tuck more often. Lots more often for the tuck! 38% and it's free?! Every ecomodder knows what that means.
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See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
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06-22-2015, 05:30 PM
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#5 (permalink)
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Master EcoModder
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I always forget that libraries share stuff like that. Good luck, and I look forward to seeing it! I'm sure the IHPVA has some stats somewhere too, but I don't feel like rooting through forty years of PDF's to find it.
As for tucks... for me it's a comfort issue. I'm much happier on flat bars than in drops. But by all means, if you're comfortable in a tuck, go for it. It's also nice that bicycle "fuel" is much cheaper than gasoline.
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He gave me a dollar. A blood-soaked dollar.
I cannot get the spot out but it's okay; It still works in the store
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06-23-2015, 09:50 AM
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#6 (permalink)
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Cyborg ECU
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Quote:
Originally Posted by kach22i
Good article, but I'm going to treat this like any other topic focused on competition.
I ride my bike for exercise, extra drag means more work, means a better work out. ...
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Yeah, I like that attitude here too. But my bike is not *just* for exercise. It also needs range for the practical purposes of 20-30 mile days climbing sometimes 4% grades for long stretches. So certain aero improvements that help me save muscle energy and battery energy for when I most need it are welcome.
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See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
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06-23-2015, 10:25 AM
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#7 (permalink)
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Quote:
Originally Posted by kach22i
Good article, but I'm going to treat this like any other topic focused on competition.
I ride my bike for exercise, extra drag means more work, means a better work out.
Just like swimming, I've just started swimming this summer and my bathing suit acts like a parachute compared to the speedos the other guys are wearing. More work (more drag) means I'll be stronger.
In boxing the training gloves weigh more than the fight day gloves for a reason.
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Unless you're deliberately holding back during a workout, lower drag won't make you not as strong. You'll just go faster on the same wattage during training.
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06-23-2015, 04:18 PM
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#8 (permalink)
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Cyborg ECU
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Aero test result (informal, unscientific)
Just did an aero experiment (not scientific). Today the wind is blowing steady at 6mph straight up a river bike path near my home on my commute. The path is flat, straight, and in great shape. I decided to informally ABABAB test my aero tuck. In calm conditions I get a little over 22 mph (approx) electric only, full throttle. I wound the throttle out and got to 20.3 MPH (approx). Then I tucked in close the the handle bar, pulled hands, elbows, and knees in, and got to 21.8 (approx). I did this over and over for probably a mile or more.
Result: I kept seeing approximately a 1.5 mph difference between upright and fully tucked position. That almost a 7% difference,
This is noticeable but not as significant as the article suggests. Reasons for that might be the wind gusts of up to 10 mph somehow messing with the results or especially the loaded pannier behind me on one side. A loaded pannier would make whatever I do up front less significant, I would bet.
__________________
See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
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06-23-2015, 04:59 PM
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#9 (permalink)
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Master EcoModder
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A good fairing system starts with a bike that fits the rider comfortably. The lower the shoulders, the less frontal area you have. The fairing guides the air around you smoothly. Just a front fairing doesn't do that well enough. My big touring style winter fairing is 1 mph slower in a coast down test (16 mph) without a matching tail box. ALWAYS mount the fairing to the frame, NOT the handlebars. That way the wind will hardly affect steering.
For safety use a rear view mirror and lights. Check the local auto parts store for light weight dual racing mirrors.
Last edited by Grant-53; 06-23-2015 at 05:17 PM..
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06-23-2015, 05:21 PM
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#10 (permalink)
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Master EcoModder
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Tucking for any length of time is very taxing. I prefer riding a recumbent, you get better aero and better endurance too.
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I'm not coasting, I'm shifting slowly.
Last edited by UFO; 06-23-2015 at 08:00 PM..
Reason: Added image
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