Building fairings

Try trimming the edge off, and also cutting down the frontal area in general. Study sport bike fairings to get a good idea of what works pretty well.
Helmet tops are reasonably aerodynamic, so no need to get the fairing really high or wide up top.

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Hey Mathurin,

Good on ya for giving it a shot.
What I found was you need to have a wind speed of 20 mph before you
start to see much. Drag was reduced about 8% in the low 20's. and only
4% at 14 mph. At 30 mph it is quite large. So go find a bigger hill and
maybe a speedo or gps or stopwatch. I'll be interested to see your numbers.

Rode to the brewery yesterday though 10-20 mph of wind. Heading into
the wind I had no problems with sidewind effects, but coming back
downwind at Rowena Dell, the high point with some really snaking curves I
had a couple times where I felt it. Not to bad of a problem, but I did brake
to slow down.
Having any sides to the fairing on a bicycle on a gusty, windy day is
probably not a good idea.

I change two things for this ride. One, having the RRF. Two, I stayed in
the 4011 mode the whole way. So I don't have any hard data on either
ideas. But 25.4 miles (with 1,200 ft vert)though 10-20 mph of wind is not bad, IMHO.

Lowell, you're absolutely right. This is Basic Research. Thanks for the
link to fluent. I checked it out. Do you have this software on your
desktop?

Later
Kyle
 
I have Fluent installed on one of my computers, but to get any useful
results from a 3D mesh can take weeks of regular PC time. Even a
relatively simple 2D airfoil analysis can take 1/2 hour for each angle of
attack. I found it far quick to build a real model and test lift/drag the old
fashioned way, along with wool tufts to indictate flow separation and
direction. Maybe if I had a supercomputer sitting idle in my shop... 8)
 
Ebike fairing V1. Take 1 pocket bike front fairing, plus a beat up CBR
screen. Power consumption went from about 2200W input, down to
1700W at 40mph. Wind noise is completely eliminated, and it's so quiet
behind the screen you could probably talk on a bluetooth headset just fine.
I think the screen is a bit too high and the fairing too small, but I'm going
to make adjustments and optimize the overall position. I moved my carry
bag off the rear rack and up to the top tube which made a positive change
to the handling and gives something to lean on like a tank fairing would.


 
Way Cool!

Thats more like it!! nice, more photos please and yes I agree that would make a significant difference to things! superb 8)

Knoxie
 
Kudos. Truly impressive results.

The RRF is still winning in the style category, but this shows a lot of bang for the buck in terms of effect v. size.

:D
 
Great, more data. :D
Any idea of the Frontal Area?
What angle of Attack?
Did you try any other speeds?

Lowell
I had no idea it would gobble up so much PC time.
I guess there is no reason to send you CAD models.
Thanks for running the one that you did.
Any idea of what differences to design for between a fairing for 25-30 mph
and the probably 50-80 mph speeds they are designing for motorcycles?

Later
Kyle
 
First real test of my fairing, and the results are not bad.

MaxS 53.4mph
AvgS 36.4mph
Wh/mile 53.1
distance 20.7 miles

Normally for this speed I would have a Wh/mile number slightly over 60, so the actual power savings is at least 10%. I was hoping for something more like 15-20% though, so more testing is in order.
 
Latest fairing/screen pics. I used a pair of old bar ends to mount the
pocket bike fairing, which hold it very securely. I bought a sheet of .040
styrene to replace what is cardboard right now, and I'm planning to cut
holes under 'Honda' to mount the headlights. The DrainBrain will find a
new home at the base of the windscreen which will make it easier to read
while tucked.




 

You are definitely on the right track. That's where I'm headed
too, to get a bicycle to be able to go 50 mph and it to be "okay"
and "normal". All you need now is a bike frame that is closer
to the 52" standard wheelbase that motorcycles use. My bike
is about 51" and it handles just like a motorcycle at speed with
no glitches at all.

:arrow: So after you complete the aerodynamics you might turn
to better bike geometry. If your bike is rear wheel suspended
you might start thinking about making a longer swingarm...
that's the most direct way to increase the wheelbase.

Once you lengthen the wheelbase you can then shorten the
stem for the handlebars. Bringing the bars back a couple of
inches will make things feel more stable. The long stems are
for better riding position not handling... It looks like you could
fit a stem that was two inches shorter...

And you might try moving the seat back an inch...

In a "perfect world" you would move the bottom bracket back
an inch too, but that means a whole new frame...
 
The shorter stem is definitely something I'm going to do now that I can sit farther back on the bike. This frame is probably not worth modifying due to the odd design, so the longer wheelbase will have to wait for the next bike.
 
TD1 Fairing Preview
TylerDurden's 1st fairing pattern
Tyler: Nice work on the "Straight Line to Curve" shaping.

I scaled the TD1F with a "wild ass guess"(WAG) and plotted it out.
Cut it out of cardboard and stuck it together with "Duct Tape" and add a "front and center" panel.
Attached with zip ties.

As it "Wind Season" around here, I don't have any numbers yet, but preliminary riding seems good.


Patterns and test results to follow.

Later Kyle
 

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You guys realise this is never ending?
After you perfect the front fairing then you start on a rear fairing to close the air smoothly behind you.
Then starts the if I had a full fairing.....

"The worlds fastest prodution bike"
F40Race.jpg
sf40blu.jpg
 
Kyle said:
TD1 Fairing Preview
TylerDurden's 1st fairing pattern
Tyler: Nice work on the "Straight Line to Curve" shaping.

I scaled the TD1F with a "wild ass guess"(WAG) and plotted it out.
Cut it out of cardboard and stuck it together with "Duct Tape" and add a "front and center" panel.
Attached with zip ties.

As it "Wind Season" around here, I don't have any numbers yet, but preliminary riding seems good.


Patterns and test results to follow.

Later Kyle
Click to expand...

I'm interested to see how that fairing compares to the RRF. Can you tuck behind the bubble with the windscreen so close?

I rode in the rain for the first time since installing my fairing/screen and it's awesome. Barely any water got on my jacket, and mostly at stop lights. Once up to speed and tucked in at 50+mph, rain drops don't stand a chance.
 
Hello everyone,

I just joined this forum. I wanted to reply to the post from May 4th, in which username 10kw posted a picture of one of my faired bikes.

I have been building fairings since 1986.

NFA Vehicles Type 5:
This bike's fairing is made of Kevlar. I used this bike while I was in the "shore patrol", the Navy's Military Police. This bike can float, so it is "amphibious". Here it is in plain gray Navy paint, with my Daughter giving her friend a ride:
Type5withPassenger.jpg
 
Here is the Type 6, which has the same basic fairing as the Type 5, with a tailbox and a roof:
Type6Velomobile1990.jpg


Type 7 is a complete re-design. The girls designed this fairing, with a lid that opens , hinged at the front. I found the best aerodynamic effect was with the top set at 53 degrees:
photo003.jpg

Here is Type 7 with the 'hood' open to 90 deg. It's nice to be able to use it as an airbrake:
photo005.jpg

Here is the mounting bracket for the Type 7:
photo008.jpg
 
Here is the Type 9:
00000024-1.jpg

Mellisa designed this bike with a spoiler based on the Kenworth truck. The previous Type 5 had such a big fairing that , when it was used in Florida, the test riders complained that it was too hot.
So the Types 7&9 have smaller fairings.
 
Holy cow...

I knew we had "the heavies" in our membership, now we have a legend.

I am certain those pix have inspired cyclists worldwide to design and build fairings.

They inspired me...

:D
 
I believe the Type 9 may have inspired others to build Electric Bikes.

I was late getting on the Internet. Computers I have owned or used:
In 1981 I bought a Sinclair ZX-81, which had a 1k memory.
In 1982, I used a computer at my High School, a Commodore PET, which had a 4k memory. I programmed it to do Quadratic Equations, so it did all my math homework in the tenth grade. Then I programmed the 4k Commodore PET to run a "Search". The Search Engine that I wrote only needed 1.27 k, while other search engines of that era used over 100k.
The High School uploaded the Search Engine to it's 22k machine and started using it to find students home phone numbers and addresses.
There was another student who lied and claimed he wrote the search engine, and to settle the argument , I was forced to give the program away as "public domain" or "share-ware". The boy who lied and said he wrote it has since died (He was in the World Trade Center on 9-11-01), so maybe I can pursue some kind of patent claim now.
In 1984, I got one of the first Apple Macintosh computers, with 128 k.
That computer kept going and going untill 1997, when it died.
I got an Imac in 1999 and finally got on the Internet.

But the Type 9 bike was photographed in 1996, while I was riding up 5th Avenue in New York City. Apparently, foreign tourists are drawn to the famous fifth avenue, and they bring their cameras. There were at least 8 tourists taking pictures with 35 milimeter cameras, including one who was using an autowinder to shoot a whole roll of film of my/Mellisas bike.
These tourists were German, Dutch, and Chinese, countries where they like bikes, and know the value of "spy-photographs", to manufacturing.
 
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