Getting Aero - Speed Gains

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lowracer

New Member
Oct 17, 2008
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Charleston, SC
I've been an avid cyclist for many years & have owned & raced many different type of bikes ranging from Road, Track, MTB, BMX, Lowracer, Tadpole trike, Recumbent...etc
On all of the bikes I've pedaled, lowering my body into an aerodynamic tuck (time trial position) has increased my speeds by reducing aero drag.
One bike I owned was known as a Lightning F40 (see 1st pic) & was basically a 3/4 faired recumbent (just head sticks out) with a fiberglass nosecone & fabric body (which I later replaced with a coroplast plastic body for better aerodynamics & speed). I estimated the Lightning F40 gained ~40% speed advantage being mostly faired (max ~30 mph unfaired, ~42 mph faired). Human powered bicycle speed records in excess of 80 mph have been set due to extreme aerodynamic bodies.
The full fairing 2 wheel bikes are awesome until the wind blows, then the sail effect causes seriously scary situations & unpractical for street use.
Recently I began surfing for aero body fairings for upright bicycles & landed on Gravity Bikes. These BMX bikes built in the 80's & 90's with very slick motorcycle type fairings to race down hills. They are making a comeback & the fairings look slick for MB applications.
I would like to build a fairing onto one of my three MB's to see what kind of aero gains are accomplished, & not just for speed but for efficiency & comfort. Smaller engine MB's could see significant gains in performance & efficiency by lowering the power required to move at any given speed.
I also added a bubble & coroplast to a tadpole trike creating a 3/4 fairing (similar, but a crude variation of the slick velomobiles available today such as the Rotovelo by Trisled (see pic). The trike handled the wind much better than the F-40 but had a lower top speed, was heavier & took up more road width.
Anybody have any ideas/comments about partial fairings and how they can be integrated onto Motored Bikes for performance, efficiency, comfort?
-Lowracer-
 

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rustycase

Gutter Rider
May 26, 2011
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Left coast
comments?

:)

I think, perhaps the quickest improvement could be gained with a front-wheel disk, clip-on low bars, and a dacron/velcro sleeve over a framework made of recycled fiberglass fishing rods and slit bamboo.

Best
rc
 

bairdco

a guy who makes cool bikes
Aug 18, 2009
6,537
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living the dream in southern california
my brother had one of those Hutch HPV's. that thing was crazy. had a giant gear,and i clocked him over 50, pacing him in my car.

i've been thinking about fairings and stuff, cause i want to go for the 50cc motorcycle land speed recordat bonneville, but it's all in my head right now...
 

lowracer

New Member
Oct 17, 2008
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Charleston, SC
Bairdco,
Going for a land speed record would be very cool!
For myself, I'm thinking of a 'Practical Street' fairing, an aero 'front only' fairing that wouldn't interfere with normal sitting/standing pedaling & would stay manageable through gusting winds.
-Lowracer-
 

andrewflores17

New Member
Jul 12, 2010
479
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colorado springs, CO
should definatley increase fuel economy i feel like a kite with my jacket on my bike somedays

id only worry about the full body design for day to day use just need a 18 wheeler going by and that gust of wind could send you flying .
 

lowracer

New Member
Oct 17, 2008
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Charleston, SC
andrewflores17,
I had a few very scary rides on the Lightning F40 some of those involving tractor trailers going by. I remember one day in particular when the wind was blowing so strong I had to ride the bike most of the time at about a 45 degree angle just to go straight.
I'm thinking of installing just a frontal fairing for my MB.
-Lowracer-
 

Allen_Wrench

Resident Mad Scientist
Feb 6, 2010
2,784
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Indianapolis
my brother had one of those Hutch HPV's. that thing was crazy. had a giant gear,and i clocked him over 50, pacing him in my car.

i've been thinking about fairings and stuff, cause i want to go for the 50cc motorcycle land speed recordat bonneville, but it's all in my head right now...
Ya know, Baird, if you decide to go after that record, I'd feel safe betting money on you. I keep hearing people on this forum saying your bikes are no slouches. Especially the ones with their jug on backwards. I say go for it.
 

The_Aleman

Active Member
Jul 31, 2008
2,653
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el People's Republik de Kalifornistan
I've personally seen Baird do 54 on GPS with a backwards jug engine. He's got the skills and the right body to go fast.

He could probably fit in some narrow fairings! I wouldn't ever be suprised to see him (and/or some other members here) on a record board :D
 

andrewflores17

New Member
Jul 12, 2010
479
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colorado springs, CO
andrewflores17,
I had a few very scary rides on the Lightning F40 some of those involving tractor trailers going by. I remember one day in particular when the wind was blowing so strong I had to ride the bike most of the time at about a 45 degree angle just to go straight.
I'm thinking of installing just a frontal fairing for my MB.
-Lowracer-
i think that just the front would give you all the benifits and almost none of losses if you do pics pics pics
 

lowracer

New Member
Oct 17, 2008
1,319
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Charleston, SC
IB...lol

DRC,
I have been on the Vetter website in the past & really like the high mpg bikes from years ago. He has a blown full body shell kit available for sale, but for me, I'm interested in just a front nose fairing to get my upper body & legs behind similar to the pic I posted of the Blue Fairing. I also like the road bike with the guy standing behind the fairing pic.
Wish there was a place to buy just that?
-Lowracer-
 

lowracer

New Member
Oct 17, 2008
1,319
2
0
Charleston, SC
Today, I got the milk crate nicely mounted using some aluminum bar & angle aluminum. Also incorporated some cheap handlebar mounts made for mounting water bottle cages to handlebars. I can now carry one of my two plastic gas cans (as large as 2 gallons) for long travels without gas stations fill-ups with extra room for stuff. Now I want to get some plastic fairing material to mount over & in front of the basket to get aero...
Still researcing blown lexan type fairings from ZZipper & Mueller, but also might just experiment with some thin plastic sheet (like those roll up snow sleds) or coroplast to create a decent shape to break the wind...
-lowracer-
 

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