Anyone use fairings? Why not...?

chas58

10 kW
Joined
Mar 19, 2013
Messages
712
Location
Detroit, Michigan, USA
A thread on efficiency got me thinking about fairings.

I ran across this:
"Numbers on the topic aren’t easy to find, but some that are regularly cited are extracted from David Gordon Wilson’s Bicycling Science. He states that a rider on a touring bike equipped with a partial fairing, and his or her hands on the handlebar, would require 63 watts less (157w vs. 220w) to overcome air resistance at 35km/h when compared with the same bike and rider without. Huge gains indeed."

Wind resistance goes up exponentially with speed, so this could make a HUGE difference on an ebike...

Maybe I should get one of these...
http://www.zzipper.com/Products/prod_upright.php

Untitled-7.jpg
 
All a small fairing like those pictured will do is keep your hands warm.

A larger fairing does allow you to go faster but is susceptible to wind gusts which can push you into traffic. There's also the PITA factor.

I commuted on a recumbent with *almost* full fairing for a year. Yes it would really stretch the distance I could go on a single charge. There were many days which were extremely scary because of the wind. Then I decided to just get a higher powered motor and lose the fairing.

Warren
 
So I am guessing that you had a clear fairing that what I will call here.. was an open fairing ?
Meaning
You had a fairing bolted on to the frame with brackets,
However
You , ... did not , .. have any fairing made of either fiberglass, or fabric that connected to the clear windshield type of fairing and then went down and around the sides and bottom of the recumbent ,
In order to direct the wind around the trike . Like the Complete front and sides of a velomobile.

That is the way to have a fairing IMHO on a Trike/Recumbent .
Something like this, the Cabirovelo, with slightly higher sides, adapted/designed for two wheels . ... https://www.trendhunter.com/trends/cabriovelo-velomobile

Look at what the Trike/Microlight Mgf's do to to the simple frame Trikes/Microlights. They have for sale what they call a " Pod " . This should be done with recumbents/trikes as well for a few reasons , you being able to go back and ride with more efficiency and with better weather protection than what you had before.







www.recumbents.com said:
I commuted on a recumbent with *almost* full fairing for a year. Yes it would really stretch the distance I could go on a single charge. There were many days which were extremely scary because of the wind. Then I decided to just get a higher powered motor and lose the fairing.

Warren
 
I had a ZZipper fairing that I used on my road bike for commuting back in the 90's. I found the benefits did not compensate for the negatives. It amplified road noise, added a little weight, was something additional to clean and care for (carefully since it might scratch), complicated using a strong headlight (reflections) and with it mounted to the handlebar, and it could affect steering in strong winds. I felt I got a greater net benefit from using inexpensive wheel covers I put on my rear wheel to turn it into a pseudo disc wheel.

With my e-bike, I'm not very interested at all in using a fairing. I have far more power than I did using only my legs on the road bike. I have no problem cruising at 25-28 mph (as fast as I desire) on my commute with a range of 40+ miles.

Likewise, I'm opting for 2" tires when narrower tires with higher pressure would be more efficient (and harsher riding). In general, with the additional electric muscle that the e-bike motor provides, it is less important to worry about areas of small efficiency improvement. OTOH, if I wanted to go 40mph and have long range, or if I were building a lightweight road bike based e-bike, then I'd probably seriously look at using a fairing.
 
I'm pursuing a semi-faired philosophy, I have a tail-box, fairing and footwells on a recumbent platform. I did not go for a complete enclosure because I don't like how noisy and flimsy full enclosures on bike platforms feel. Also,I was looking for ease of entry and exit and a swing-away front fairing suited that best.
One of the great things about electrifying a bike platform is that the extra power allows for heavier and better thought out fairing components.
My vehicle handles cross-winds very well, does not rattle and is much more pleasant to ride at high speed in bad weather than any other bike I have had before. if you want to check it out, the build post is in my signature line
 
tigcross said:
My vehicle handles cross-winds very well, does not rattle and is much more pleasant to ride at high speed in bad weather than any other bike I have had before. if you want to check it out, the build post is in my signature line

Yes. I've looked at your project. It is very cool and well thought out. It also crosses into a realm, in my mind, of being a bit beyond a mere e-bike and into being something closer to a regular vehicle. A fairing on your "bike" seems very sensible.
 
Hey chas58, having looked more carefully I see that your question was specific to upright bikes. On that front I tried one on my electrified cargo bike which had a top speed of about 50 KPH. It was nice at speed, but not worth the hassle of getting it into the garage and bike racks. I took it off after a few months. I do enjoy the fairing on my Electrom, but I think of it as more of a vehicle than a bike and It doesn't park in bike racks.
 
Rather than a windshield type fairing, I did try out some body-fairings for CrazyBike2, mostly to keep the rain off the electrical bits.

They weren't exactly slipstreamers ;) but they made some small difference in the wh/mile. Given that I still had the two big cargo boxes on the back turning the bike into a rolling brick wall, I was surprised it made any difference. :)

I've considered something for the SB Cruiser trike, but anything that would really help would almost have to enclose the whole thing, and that would be unbearable in the weather here for half the year or more.

But I actually have two motorcycle windshields that I have thought about mounting on there to keep the winter chilly wind out of my face, that I could test to see if it makes any difference--if it could push the air up over and around the canopy over my head it would probably make a dent in the power usage that thing adds.

Since I need to rework the tiller anyway, for some other things, then next chance I get perhaps I'll add mounts for one of the windshields, and do some tests.
 
Oh, and there have been a few fairing discussions over the years, so if any of the info in them is useful, most are listed here
https://endless-sphere.com/forums/search.php?keywords=fairing&terms=all&author=&sc=1&sf=titleonly&sk=t&sd=d&sr=topics&st=0&ch=300&t=0&submit=Search
though not everything in that list is relevant, it's fairly obvious which are not. ;)
 
The main thing about a fairing, is you need to be all the way behind it. If you sit up instead of crouching behind it, you lose a lot of the effect.

When I got my Yamaha 400 scooter last year, I loved the full fairing on it. even the legs and feet were in the slip stream. But I noticed my helmet still made a lot of noise, unless I crouched lower. The slipstream over the top of the windshield hit my helmet just above the eyebrows, making it too loud, at 90 mph. Wind was whistling around the gaps in the face shield.

So I taped some clear plastic to the windscreen, raising the windscreen 4 inches. Still loud at 90, but now very comfortable at the 75 mph speed limit. I thought for sure I had cost myself some aero with the tall windshield, but to my surprise, I found my top speed increased 5 mph! From about 93, to 98. And gas mileage went from 58 to a solid 62 mpg. ( at 75 mph)

I was quite shocked at the effect that a tiny bit of my head in the wind had. Much less effect at bike speeds of course, but still, if your chest and head are not in the slipstream, your fairing might not have much effect.

Nothing wrong though, with keeping your body and hands warmer with a fairing in winter!!!!!
 
Chas58, I forgot you are in / near Detroit.

If I lived there I would at least try one of those windscreens/fairings that you show.

Wonder how long it will be until you will be looking at making a velomobile ? , at least a recumbent with enough of a fairing to get the cold Fall/Winter/Early Spring , wind off your whole body, including over your head.
You do not have to make it as low to the ground and too laid back of a position .
 
Wrote this topic a few years ago: https://endless-sphere.com/forums/viewtopic.php?f=3&t=63812

Here is an explanation of my complete tailbox project:

http://renewableenergyspace.blogspot.com/2012/11/inexpensive-lightweight-recumbent.html?m=1

Energyi
 
^^ I lust... :mrgreen:

BTW... ES "Search found 1749 matches: +aerodynamic" :wink:
 
Bunch of ideas here:
https://www.google.com/search?q=bicycle+fairing&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiAmqvqqK3XAhVnqlQKHYaaB6YQ_AUICygC&biw=1536&bih=749&dpr=1.25#imgrc=_

Some of them look not-so-practical. This one seems a bit heavy:

MC fairing.jpg

This one goes way back. Looks like it would deter tail-gaters:

egg fairing.jpg
 
If you live where there are significant side-gusts of wind, a full fairing from front to rear (like the yellow velo posted above) would struggle to run a straight line in traffic. This was verified by Craig Vetter during the short time he was posting here.

Adding a "tail-sock" was found to add as much aero drag-reduction as a front fairing, but...if was only going to have a front or rear fairing, I'd definitely start with a small front fairing just for the comfort it adds.

I don't use any kind of fairing because I think it would draw too much attention, and my rides are pretty stealthy...
 
If I found something ready-made that I could simply attach to the front of my bike I would go for it. But to design, build, and deploy something from scratch would cost many times what my bike is worth. I could probably glue a couple of boogie boards together together at the nose and wire them around my front basket with a cut apart large brightly colored traffic cone for a lid, but that's the best I can think of at the moment inspired by the road kill I have seen over the years. :)
 
spinningmagnets said:
Adding a "tail-sock" was found to add as much aero drag-reduction as a front fairing, but...if was only going to have a front or rear fairing, I'd definitely start with a small front fairing just for the comfort it adds.

Back when I was commuting on my road bike in the late 80s and 90s, I had the idea to build a rear trunk by laying up some carbon fiber or fiberglass in an abbreviated tail sock shape. Even early mornings here aren't horribly cold and a front fairing could actually be extra uncomfortable in the middle of our very hot summers.
 
I liked my yellow fairing. It was very visible but very scary on those very windy days. Really the only practical fairing for road use is a velomobile type fairing. These are not affected badly by crosswinds. This means a 3 wheeled recumbent bike with a full body. Fiberglass / CF is best but inexpensive coroplast fairings work fine on trikes and are are a great platform for electrification. Even the velomobiles are not recommended for high traffic areas. You have to be even more of a badass than an urban ebike rider. Upright highly maneuverable e-bikes with highly visible riders fit better into those environments.

I just ride unfaired ebikes now. In cold weather I have a helmet with earflaps, ski goggles and face protection, plus proper clothing and gloves. It uses more power than a faired bike but is arguably safer and easier to park/stash.

Warren
 
spinningmagnets said:
If you live where there are significant side-gusts of wind...

Oh Goody! An "assist to my assist"...
140815111836-landsailing-yellow-entertain-feature.jpg


:mrgreen:

EDIT: Folks are of course welcome to ignore sources of FREE ENERGY... just hard to ignore stuff like gravity. See "hydro". ;)
 
This one looks interesting

http://www.bikeradar.com/road/gear/article/bicycle-fairing-50204/

eBike fairing.jpg
 
Unfortunately, some may have "seen the light" and gone "recumbent" featuring stuff like a big, comfy seat... a backrest... more "aero"... drink holders... etc... so "velomobile-style" ... where more "aero" features stuff like warm and dry as a thin shell... kinda addictive once yah have tried... (sorta like bettery-electric assist...) :mrgreen: :wink:
 
I want to create a blow up streamliner JACKET. IT could have cooling channels, like our helmets. No matter your posture, you would be covered. When you got to destination, just deflate. And pack. This, in conjunction with a small front fairing, and you would have no crosswind problems, and good streamlining.
 
So... how large is your bike?

turtle-gts-inflatable-cover-395.jpg
 
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