I've used Zzipper fairings
(
http://www.zzipper.com/Products/prod_upright.html) and Tailwind panniers
(
http://www.angletechcycles.com/accessories/techwind.htm) on my upright
bikes for 20-25 years.
The Winter 1990 issue of the journal Human Power published a coastdown study
I did. I compared three handlebar fairings, the Tailwind panniers, a rear
wheel cover, plus some small fairings I'd made from styrofoam and balsa for
the frame, seat, etc.
The results were that the handlebar fairings improved my speed 0.5-0.75 mph
around 20 mph, 1-2 mph around 30 mph, and 3-4 mph at 40 mph. These fairings
weighed 0.5 to 0.75 pounds.
Fitting the fairing is important: you want the fairing to fit as close to
you as possible, and to come up to your shoulders. From the side, the
fairing should center on the bowl of your lap, which is what catches the
wind. The Zzipper is usually mounted too low and too far forward to be
optimal.
The Tailwind front panniers increased my speed 0.25 mph around 20 mph. The
rear panniers (which are larger) didn't change my speed.
I forget what the wheel covers and other stuff did.
What I have on my commuting bike now is the Zzipper, Tailwind front and rear
panniers, and an Arundel aero water bottle
(
http://www.excelsports.com/new.asp?page=8&description=Chrono+Aero+Carbon+Ca
ge+and+Bottle&vendorCode=ARUNDEL&major=3&minor=12). I recall a study in
Bicycling magazine around 1975 and another by Shimano in the early 1980s
finding the water bottles add surprising drag. Spending $60 on an aero water
bottle seems like a no-brainer.
Here's picture of my bike (without the aero water bottle):
http://www.casafuturatech.com/Personal/tricross-web.jpg
I don't notice that the fairing interferes with cooling in hot weather. At
25+ mph there's plenty of wind to cool me. In the winter the fairing is a
big plus.
When winds are gusting over 50 mph I take off the fairing (four wing nuts),
roll it up and stuff it in the panniers.
I get compliments on my bike every day. Lots of people say it's the coolest
bike they've ever seen, or ask where they can get one. The strange thing is,
these compliments are from casual cyclists. The "jersey pro" cyclists won't
give me the time of day. A good friend whom I run with every week is the
buyer for one of the largest bike websites. He bike commutes every day, is a
national champion racer, owns six bikes, etc. He knows bikes and he knows
what sells. I offered to let him borrow my bike for a week. He wasn't
interested. We had a long talk about it. Aerodynamics are pointless for
casual cyclists, who are happy to tool along on a mountain bike at 8 mph.
Just pumping up their tires would make them go faster, but they don't do
that. Casual cyclists are also very price-conscious. The owner of Zzip
Designs and I had a long talk. At $175 he can't get his fairings into bike
shops. A bike manufacturer was ready to buy 10,000 fairings, but they wanted
to pay something like $10 each!
The "jersey pros" won't use fairings because they want to look like their
pro racer heroes. The crazy thing is that they want to look like bike racers
even when they're on a recreational ride, or commuting to work! They refuse
to put panniers, fenders, lights, or fairings on their bikes. They carry
what they need in a backpack or a messenger bag. They drive to work if it's
raining. They endanger their lives riding at night without lights. They ride
slower because they won't use fairings.
"Pro" bikes are made so that you can't put on panniers, fenders, etc. I went
into a large bike shop last year and they had no bikes that could take front
panniers!
But there's a parallel universe, called recumbents. In that world (where
I've heard Al Gore is President), fairings are common accessories. Panniers,
lights, and fenders are seen on bikes that go fast. I've almost bought a
recumbent several times, and I'm sure I will some day, but this is getting
long so I won't go into all that.
My friend and I agree about something: we'd love to see more people get out
of their cars and bike to work. I suggested that his website sell bikes like
mine. No one makes such bikes. (Putting my bike together took months.) I
said that if fast commuting bikes were available, people would buy them. He
said that it'd take far too much resources to sell to a niche market. We
agreed that the only thing that will change this situation will be gas
prices going over $5/gallon.
--
Thomas David Kehoe
Work:
http://www.casafuturatech.com
Not work:
http://www.myspace.com/43380153
in article
[email protected],
[email protected] at
[email protected] wrote on 6/14/06 10:39 AM:
> I like to periodically check in on this topic.
>
> What with all the aerobars, aeroframes and aerowheels out there, I'd
> think that further streamlining and fairing would be developed for
> upright bikes to whatever extent proved most effective.
>
> The fretting about removing the cooling breeze is a red herring.
>
> The worries about race rules are likewise lame---99% of riding is in
> non-events. Everyone likes more easy speed.
>
> A simple "bullet" under an aerobar might really give a nice boost (and
> place to store water, food, spare/tool). Same with a compact "bulb"
> behind the saddle---if a push-plate is included that might be something
> helpful to shove against sometimes.
>
> Then there's filling in the area between seat and dropouts to
> streamline the rear wheel. Maybe putting little shells around the
> derailleurs. What about a faired pedal?
>
> Could some kind of narrow fairing attached to the fork improve airflow
> around legs?
>
> Any simple way to give a jersey a streamlined boost? (Maybe "batwings"
> under the arms.)
>
> I'd think that maybe a couple pounds of carbon add-ons could give a few
> mph of free speed. Not bad.
>
> --JP
> allbikemag.com
>