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Upright Mike
human power expert

USA
3463 Posts

Posted - 01/14/2012 :  06:52:12  Show Profile  Visit Upright Mike's Homepage  Reply with Quote
Will - it would be nice to market an upright fairing with a bodysock, perhaps even aero-boots could be part of the kit. As far as I know, the Aero-Edge was the only body-sock upright kit marketed. Zzip designs marketed and I believe still markets the Zzipper upright fairing. Breeze-Eze and Breezecheater were also upright fairings marketed without a bodysock addition. I own a Breezecheater. I believe the AeroEdge was based off of its mold shape, but turned upside down and truncated. This was from a conversation I had long ago.

As far as turning in winds, the wind can catch the sock and cause some instability. The sock can act as a parachute. There's two ways for it to catch air. Primarily it would catch it on the side that your turning into or where the cross-wind is coming from. Say this is from the left, then the left side catches it, blowing the fabric inwards. But with the open area at the legs and the neck, the right side can also fill with air, and blow the fabric outwards like a balloon.

I added a zipper (actually my mom long ago) to the upper opening of the sock between the fairing and my head. This helped make it more controllable. There was less air scooped up. The wind noise around my ears increased. Whats disappointing is that I couldn't see my speedometer anymore.

The fabric does not tug significantly on the handlebars, but yes it does resist turning. But it acts like a steering damper which is good for me, because I have only an aerobar under my fairing. I don't have a full drop bar or anything with a wider stance to grab for better control. There is a short cut-off section of a straight-bar just under my flip-up aerobar elbow rests. I use this section to grab onto when starting out in a Kilo sprint.
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Upright Dave
New Member

USA
63 Posts

Posted - 01/29/2012 :  18:59:41  Show Profile  Reply with Quote
Here's a 20" wheel upright fairing bike. The cockpit shot is a different bike but shows the mounting.








Edited by - Upright Dave on 10/28/2012 16:27:34
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Upright Dave
New Member

USA
63 Posts

Posted - 01/31/2012 :  18:19:19  Show Profile  Reply with Quote
quote:
Originally posted by Upright Mike


As far as turning in winds, the wind can catch the sock and cause some instability. The sock can act as a parachute. There's two ways for it to catch air. Primarily it would catch it on the side that your turning into or where the cross-wind is coming from. Say this is from the left, then the left side catches it, blowing the fabric inwards. But with the open area at the legs and the neck, the right side can also fill with air, and blow the fabric outwards like a balloon.

I added a zipper (actually my mom long ago) to the upper opening of the sock between the fairing and my head. This helped make it more controllable. There was less air scooped up. The wind noise around my ears increased. Whats disappointing is that I couldn't see my speedometer anymore.

The fabric does not tug significantly on the handlebars, but yes it does resist turning. But it acts like a steering damper which is good for me, because I have only an aerobar under my fairing. I don't have a full drop bar or anything with a wider stance to grab for better control. There is a short cut-off section of a straight-bar just under my flip-up aerobar elbow rests. I use this section to grab onto when starting out in a Kilo sprint.



Another question! About the body sock again. So once you add the sock to the existing aerobars+fairing, you get an additional 1.5mph?

Also, say I wanted to complicate the installation of this and attach it to the edge of the fairing rather then pull it over it. Does anyone know how they attach spandex to lexan/petg like on the F40 or other spandex socked recumbents?
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Upright Mike
human power expert

USA
3463 Posts

Posted - 02/01/2012 :  06:14:10  Show Profile  Visit Upright Mike's Homepage  Reply with Quote
Hi Dave, yep that's right - I got about another 1.5 mph by adding the bodysock. I've found that that front fairing by itself had really a minor impact. I did coast down tests where my following terminal speeds were like this
1) Aerobars only: top speed 21.5 mph
2) Aerobars + front fairing: top speed 21.5 mph
3) Aerobars + front fairing + bodysock: top speed 23.0 mph

This was about the same difference I felt in my cruising speeds too, about 1.5 mph increase.
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Upright Dave
New Member

USA
63 Posts

Posted - 02/03/2012 :  05:33:52  Show Profile  Reply with Quote
I've done some coast down runs. The HPV chart seems pretty close to what I've experienced. Recently, I went 34.7mph coasting down a 5% grade where the chart says 33.9mph on the drops. A faint headwind too. My bike does weigh 30lbs with everything on it so slightly more speed. On the flat, I get 31.3mph on one road, then 32.6mph on another. Depends on the undulations. I need more power! Any advice?

[URL=http://imageshack.us/photo/my-images/192/dragchart3large.jpg/]
[/URL]

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Grant-53
New Member

USA
51 Posts

Posted - 03/17/2012 :  15:40:06  Show Profile  Reply with Quote
For a number of years I have been working on commuter bike fairings. One design is a front piece made from a 24" x 48" x 4mm Coroplast cut and overlapped to resemble the Vetter Windjammer. The fairing covers from knee to shoulder and attaches to the down tube with zip ties. The height can be adjusted by tightening a cord attached at the top corners and the frame. I used this for a youth technology program and a 12 yr. old could put together in a couple hours or less.
The second design is a nose cone and tail piece both secured to the frame of my Jamis Aragon with U-bolts to the head tube and seat tube. The front cone is 21" dia. and 31" long made from 1 inch hex steel mesh (chicken wire) bonded between two layers 5 mil tarp material. The rear is just a large plastic waste basket for now. The support spars are 1.5" aluminum angle. The fact that the nose is mounted to the frame and both have circular cross sections has made for very little crosswind input. If anyone is curious I have some pictures on Photobucket.
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Upright Mike
human power expert

USA
3463 Posts

Posted - 03/18/2012 :  07:34:47  Show Profile  Visit Upright Mike's Homepage  Reply with Quote
Hi Grant,
Welcome to the recumbent forums. Your design sounds nice. If you want, you can post a html link to it here. I think you need 10 posts on this forum, before you can post an image link where it will display here.
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Grant-53
New Member

USA
51 Posts

Posted - 03/18/2012 :  15:27:53  Show Profile  Reply with Quote
I have used a top tube and seat post clamp from a scrap steel frame as a support for a rear tail box on a bike with an internal brake hub to relieve some of the weight on the axle.
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Grant-53
New Member

USA
51 Posts

Posted - 03/18/2012 :  15:41:49  Show Profile  Reply with Quote
Using the wire/tarp laminate has a weight advantage over rigid fiberglass with out the mess. Cut out a section of materials and apply contact adhesive to both pieces of plastic. Assemble the layers and press together with a paint roller or broom. The surface finish is not as smooth since the plastic is glued together in the spaces of the mesh. One side can be flatter if you roll it out on a hard surface.
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Grant-53
New Member

USA
51 Posts

Posted - 03/19/2012 :  07:46:31  Show Profile  Reply with Quote
OK. I think I have enough posts without being annoying. My albums are at http:/s1187.photobucket.com/albums/z385/wgconnor
Hope they are food for thought. Dave, could you give us some more detail on making your wheel covers? I would like to incorporate them in my next build.
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alevand
human power supergeek

USA
1900 Posts

Posted - 03/22/2012 :  09:00:24  Show Profile  Visit alevand's Homepage  Reply with Quote


C:
Tony Levand
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Upright Mike
human power expert

USA
3463 Posts

Posted - 03/22/2012 :  09:53:55  Show Profile  Visit Upright Mike's Homepage  Reply with Quote
Here's my build process for laminated posterboard wheel disks
http://s47.photobucket.com/albums/f152/uprightmike/Wheel%20disks/

Basically I take a piece of posterboard, cut out a circle just smaller than the rim, slot it, so can assume a cone shape. Then I laminate the piece at Office Depot or FedEx Kinkos using the SOFT laminate. I trim off the laminate about a 1/2 inch beyond the cardboard. This is the piece that I can glue or tape to the rim. Its soft and flexible. The rest of the disk where the cardboard is stiffer. I can also avoide tape at the rim completely, and just carefully tape the disk to the spokes, by reaching in behind the disk. I use 1" strips of gorilla tape, not duct tape which can peel up in heat. Cut the corners to avoid it peeling up even more so. I've had the taped on disks last through two years of riding and rain. I've also had one streamliner at Battle Mountain use them up reaching 67 mph, and they didn't blow off!
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Grant-53
New Member

USA
51 Posts

Posted - 03/23/2012 :  15:10:24  Show Profile  Reply with Quote
Thanks, I'll try using my stash of materials to come up with something similar.
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Upright Dave
New Member

USA
63 Posts

Posted - 04/18/2012 :  20:43:17  Show Profile  Reply with Quote
My rear disc is just abs plastic 1/32". The front is fiberglass and took so much time to make that I don't recommend doing it unless you want to go insane. It has a gasket and seals everything air tight/noise free. I made it during winter using a plaster mold and it has yet to be proven effective. Its warmer now so I'll be able to get out early when the winds are calm and see if I can measure any time differences in my route.





Edited by - Upright Dave on 10/28/2012 16:27:00
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Grant-53
New Member

USA
51 Posts

Posted - 05/23/2012 :  20:46:19  Show Profile  Reply with Quote
What has intrigued me about the upright aero tuck vs a recumbent is that the unfaired versions are roughly equal in effective drag.
So a bike and shell for an upright would be lighter than a similar recumbent to produce the same gain in efficiency. It may be unlikely an upright would be competitive at Battle Mountain time trials, but in road races the upright stands a better chance. Below the knees the legs can be exposed and faired rather than extending the fairing to the ground. Most likely a faired upright is going to be used for commuting and touring provided a comfortable saddle is used. A full suspension bike may be desirable when cruising at 30 mph.
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Speedbiker
human power expert

USA
2467 Posts

Posted - 05/23/2012 :  22:33:18  Show Profile  Reply with Quote
Dream on, Grant...
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Grant-53
New Member

USA
51 Posts

Posted - 06/14/2012 :  21:12:20  Show Profile  Reply with Quote
I am past dreaming and ran the numbers. Construction is underway for a 30 mph street bike. A racer would want to go 45 to 50 mph.
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Upright Dave
New Member

USA
63 Posts

Posted - 07/18/2012 :  14:40:52  Show Profile  Reply with Quote
Ok, that was 1 month ago, you done yet Grant?
I'm going to keep working on my engine and eating "power foods". I'm getting faster. No reason to build a practical streamliner yet. I'll save my money.
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Larry Lem
human power expert

South Sandwich Islands
2302 Posts

Posted - 07/18/2012 :  15:00:30  Show Profile  Reply with Quote
"What has intrigued me about the upright aero tuck vs a recumbent is that the unfaired versions are roughly equal in effective drag."

I think Unfaired recumbents can have less effective drag than an aerotuck upright.

So a bike and shell for an upright would be lighter than a similar recumbent to produce the same gain in efficiency.

Same gain in efficiency....How do you draw that conclusion? Missing a premise or two.

Larry Lem
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Grant-53
New Member

USA
51 Posts

Posted - 07/23/2012 :  22:07:09  Show Profile  Reply with Quote
The front touring fairing is on my Jamis Aragon and I went from 11 mph to 14 mph at casual cruise output. Remember I am 58 years old and weigh 250 lbs. I am a commuter not a racer. My premise is based on the data found in the article "The Aerodynamics of Human-powered Land Vehicles" by Gross, Kyle, and Malewicki. The powered required for 20 mph on level ground is nearly identical for the racing crouch bike with aero components (73% of baseline - standard touring bike) and the Easy Rider (75%). Add a tail such as The Rocket by Oscar Egg to Mike's 2010 design and you have a light weight shell mounted to the head tube with an aspect ratio 1:4. At higher speeds the recumbent has an advantage of a better aspect ratio especially if the rider's back is close to horizontal. Still, to get the coefficient of drag reduced by 50% will require more material for the recumbent shell. Dave, the cost of materials for the touring fairing is under $10 USD, not bad for a 27% increase in speed first time out. No problems with side winds since it mounts to the down tube. Pictures and more data to come.
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Speedbiker
human power expert

USA
2467 Posts

Posted - 07/23/2012 :  23:01:37  Show Profile  Reply with Quote
Good thing you used the latest data. Better off talking to Mr Mowett about the virtues of "modern" recumbent design as compared to upwrongs(faired or otherwise). He has more practicle experience with a highly evolved, very modern, semi faired df than most anybody. So, what is he riding now that is much faster and infinitely more comfortable?
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warren
human power expert

USA
4902 Posts

Posted - 07/24/2012 :  05:52:58  Show Profile  Visit warren's Homepage  Reply with Quote
I think what Thom is trying to say is that the Easy Racer is not very aerodynamic in comparison to modern racing recumbent bikes.

It probably does compare well to modern "comfort" recumbent bikes.

-Warren.
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Upright Mike
human power expert

USA
3463 Posts

Posted - 07/24/2012 :  13:28:58  Show Profile  Visit Upright Mike's Homepage  Reply with Quote
Keep up the good work guys! Yes, I am a bent-head now (because I've finally exceeded my best speeds on a upright with bodysock fairing, actually by alot!), but I still catch myself looking at my upright thinking about making it faster. I am enjoying your progress and ideas. Speedbiker is a good friend of mine, and I hope you know we're just having fun (and not being mean to you!) and poking fun at the 130 year old and slow upright bike!! We wish the UCI hadn't outlawed 'bents back in 1934, else we might have been riding them today! It took me awhile to make the switch (actually after about 20 years in this club), but it was worth it!

By the way, in the Battle Mountain thread I just learned today that Jim Glover, the fastest upright bike fairing guy of all time with a full-faired Moulton, will be coming to Battle Mountain this year, presumably to spectate or volunteer? I'm not sure if he's dusting off his old bike yet, but if he is, it would be very very interesting to see how fast he could go on the course. He went 51 mph back in 1986 on a sea-level course.
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Grant-53
New Member

USA
51 Posts

Posted - 07/24/2012 :  14:32:07  Show Profile  Reply with Quote
Just so you all know, I live 65 miles from the Bicycle Man, Pete Stull, who produces the Linear LWB recumbent. We have been friends for years and I have ridden the Linear. It has a high enough seat, 20 inches, so the rider can be at the same eye level as a passenger car driver. Trikes and other 'butt scrapers' can be fun just not in traffic. The secret to comfort on a bike is proper adjustment and component selection. The Jamis seat is very well designed for comfort. Fifty years of riding didn't prevent me from siring five amazing children;). The best I would expect from a competition upright at Battle Mountain would be 60 mph and 45 mph in a tight road course or drag race. With ten years experience in customer service selling auto parts I have a thick skin and a quick wit. Don't harass the parts man until after he totals your bill-he can always add another 10% for abuse! My favorite is the line by the comedian Sinbad, "Does your mother even LIKE you?"
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mhelander
recumbent enthusiast

Finland
352 Posts

Posted - 07/25/2012 :  13:15:53  Show Profile  Reply with Quote
quote:
Originally posted by Upright Dave

My rear disc is just abs plastic 1/32". The front is fiberglass and took so much time to make that I don't recommend doing it unless you want to go insane. It has a gasket and seals everything air tight/noise free. I made it during winter using a plaster mold and it has yet to be proven effective. Its warmer now so I'll be able to get out early when the winds are calm and see if I can measure any time differences in my route.



I've tried little different approach. Used Chinese full-carbon 60mm deep rim (complete wheel) as male mold to make two half. Used kitchen wrap plastic to protect rim & spokes and mattress foam to compress fiberglass over inner edge between spokes.

Some bulges and not so good inner edge. Then disassembled Roval 18sp radial front wheel, taped two half to rim and started gluing together from inner edge. When partially joined then used 2" fiberglass strip to seal inner joint.

Next to cut out bulges, patch with fiberglass and apply second layer on top. If surface is roughly ok, gluing fairing to rim.

Then likely some polyester putty for smooth surface and black paint.

As said, overly too laborious to make. Would be much, much easier over non-built deep rim. Luckily I'm not going to build another.

Now I have combination wheels with 60mm rims both front & back, and converted Hope Pro III & Arc en Ciel wheel permanently to disc wheel with spandex & epoxy & fiberglass. And lowracer's front 451 spoked wheel has full fairings too, removable as used elastic acrylic glue to bond those to rim.

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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