Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 09-29-2020, 01:29 PM   #21 (permalink)
Master EcoModder
 
Join Date: Jan 2008
Location: Sacramento, CA
Posts: 396
Thanks: 31
Thanked 135 Times in 99 Posts
Quote:
Originally Posted by JulianEdgar View Post
The requirement was for a commuter bike, and - if we're up for outright low drag - a recumbent velo would kill a time trial bike.

(Basically all fast, low-drag pedal machines are banned from competition. It gets me very cross, because people then assume that fundamental bicycle tech stopped in about 1920.)

This is state of the art in low drag cycling, not a time trial bike...



It still brings me out in goose pimples watching this:

You should see what happens when it hits 88 mph.



JJ

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 09-29-2020, 01:37 PM   #22 (permalink)
Master EcoModder
 
Join Date: Jan 2008
Location: Sacramento, CA
Posts: 396
Thanks: 31
Thanked 135 Times in 99 Posts
For more upright fairings than you may ever want to see. Visit this long thread. I see that many of the photos no longer exist, but there are still a few around.

The Recumbent Bicycle and Human Powered Vehicle Information Center

JJ
  Reply With Quote
The Following User Says Thank You to jjackstone For This Useful Post:
Grant-53 (09-29-2020)
Old 09-29-2020, 04:18 PM   #23 (permalink)
Master EcoModder
 
Join Date: Nov 2017
Location: Australia
Posts: 991
Thanks: 62
Thanked 863 Times in 563 Posts
Quote:
Originally Posted by jjackstone View Post
For more upright fairings than you may ever want to see. Visit this long thread. I see that many of the photos no longer exist, but there are still a few around.

The Recumbent Bicycle and Human Powered Vehicle Information Center

JJ
I see the OP is a contributor to to that thread so he's probably aware of all of the designs (even when the pics worked)!

But it gives me a chance to post these:



  Reply With Quote
The Following User Says Thank You to JulianEdgar For This Useful Post:
Grant-53 (09-29-2020)
Old 09-29-2020, 06:29 PM   #24 (permalink)
Master EcoModder
 
Join Date: Feb 2010
Location: Elmira, NY
Posts: 1,709
Thanks: 302
Thanked 320 Times in 267 Posts
Uprightdave did display a road bike that used a Zzipper front piece and lycra stretched over a foam tail section. He cruised at 27 mph. I have a photo somewhere. I also have a National Aerocargo front piece that attaches to the handlebar and fork. It is the combination of a nose cone and a tail section that gives the best results. Sailplanes use either a space frame and aluminum skin or a composite monocoque. The SZD-9 bis Bocian 1E sailplane plans are available free (sheet 1) and I would look at making the Kamm tail at bulkhead 6.

Last edited by Grant-53; 09-29-2020 at 06:39 PM..
  Reply With Quote
The Following User Says Thank You to Grant-53 For This Useful Post:
skyking (09-29-2020)
Old 09-29-2020, 06:41 PM   #25 (permalink)
Master EcoModder
 
Join Date: Feb 2010
Location: Elmira, NY
Posts: 1,709
Thanks: 302
Thanked 320 Times in 267 Posts
The Moulton faired bikes hit 50 mph.
  Reply With Quote
Old 09-29-2020, 07:21 PM   #26 (permalink)
Master EcoModder
 
Join Date: Nov 2017
Location: Australia
Posts: 991
Thanks: 62
Thanked 863 Times in 563 Posts
Quote:
Originally Posted by Grant-53 View Post
The Moulton faired bikes hit 50 mph.
Just over, in fact.

  Reply With Quote
The Following User Says Thank You to JulianEdgar For This Useful Post:
Grant-53 (10-01-2020)
Old 10-01-2020, 10:48 AM   #27 (permalink)
Master EcoModder
 
Join Date: Feb 2010
Location: Elmira, NY
Posts: 1,709
Thanks: 302
Thanked 320 Times in 267 Posts
One design criteria is easy ingress/egress. I am 67 yrs and throwing a leg over the top tube of a diamond frame is difficult. If I want a full shell then I can add side doors to my current design on a step through frame. The other option is to have a one piece shell that hinges near the nose and rotates forward.
As for a clear windscreen I would look for a piece from a motorcycle sport bike.
  Reply With Quote
Old 10-01-2020, 04:42 PM   #28 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 17,184
Thanks: 4,600
Thanked 5,751 Times in 4,586 Posts
Quote:
I am 67 yrs older and throwing a leg over the top tube of a diamond frame is difficult.
I've go a scar on my left elbow for proof.
__________________
.

We are operating at an overall mechanical efficiency of only four percent… Therefore, we find that if we increase the overall mechanical efficiency to only twelve percent we can take care of everybody. That three-fold increase in the overall efficiency can only be accomplished by redesign. – R. Buckminster Fuller

_________________
  Reply With Quote
Old 10-02-2020, 03:34 AM   #29 (permalink)
Master EcoModder
 
Join Date: Nov 2017
Location: Australia
Posts: 991
Thanks: 62
Thanked 863 Times in 563 Posts
I think it's probably time to start building and testing your ideas!

It sounds like you're aiming for a step-through (lady's?) bike with a development of what you've already been trialling in the coroplast.

I'd be using a blown acrylic dome and lightweight frame (laminated plywood strips?) with stretchy cloth and zippers, on one or other of these:



(My restored/modified 1960s Moulton "billiard cue")

or



(My work-in-progress Moulton space frame.)

But neither is common or particularly attractive to many people.

Good luck - I think it is a great project. (I never realised how hard it is to improve the efficiency of a machine until I started working on pedal-powered vehicles... makes car stuff look easy.)
  Reply With Quote
The Following User Says Thank You to JulianEdgar For This Useful Post:
Grant-53 (10-03-2020)
Old 10-02-2020, 12:03 PM   #30 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 17,184
Thanks: 4,600
Thanked 5,751 Times in 4,586 Posts
Quote:
(I never realised how hard it is to improve the efficiency of a machine until I started working on pedal-powered vehicles... makes car stuff look easy.)
Quote:
“When one compares the energy consumed in moving a certain distance as a function of body weight for a variety of animals and machines, one finds that an unaided walking man does fairly well (consuming about .75 calorie per gram per kilometer), but he is not as efficient as a horse, a salmon or a jet transport. With the aid of a bicycle, however, the man’s energy consumption for a given distance is reduced to about a fifth (roughly .15 calorie per gram per kilometer).

“Therefore, apart from increasing his unaided speed by a factor of three or four, the cyclist improves his efficiency rating to No. 1 among moving creatures and machines.
www.bikeboom.info/efficiency/: How the bicycle beats evolution and why Steve Jobs was so taken with this fact

I like the space frame. Can you use the trusses as a luggage rack?

__________________
.

We are operating at an overall mechanical efficiency of only four percent… Therefore, we find that if we increase the overall mechanical efficiency to only twelve percent we can take care of everybody. That three-fold increase in the overall efficiency can only be accomplished by redesign. – R. Buckminster Fuller

_________________
  Reply With Quote
The Following User Says Thank You to freebeard For This Useful Post:
COcyclist (10-18-2020)
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com