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warren
human power expert

USA
6454 Posts

Posted - 04/22/2012 :  18:07:31  Show Profile  Visit warren's Homepage  Reply with Quote
Is that one of your builds, Tom?
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rzon
Starting Member

USA
10 Posts

Posted - 04/23/2012 :  04:30:09  Show Profile  Reply with Quote
The bike has 26" wheels , the frame is made from 1.75 x.035 ovalized. The fork angel is being changed to 66-67 degree. Shorter tiller, hopefully will stop the fork from bending back, better vision.
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tom porter
recumbent enthusiast

161 Posts

Posted - 04/23/2012 :  07:49:00  Show Profile  Reply with Quote
Not one of mine Warren but similar to a bike I had about 2004. Don't know who Rzon is, maybe he could tell some more about himself.

O---o
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Patrick Bateman
New Member

USA
70 Posts

Posted - 04/26/2012 :  10:44:17  Show Profile  Visit Patrick Bateman's Homepage  Reply with Quote


Larry's bike has inspired me to finally figure out how to do a bike in Pepakura. Stay tuned to this thread here to watch the progress:

http://www.bikeforums.net/showthread.php/812337-stringbike
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Ivo.M
Starting Member

Germany
31 Posts

Posted - 05/03/2012 :  08:19:29  Show Profile  Reply with Quote
For your inspiration and/or entertainment: A Flevobike construction, dating back to about the mid- 1990s of the last century.


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Larry Lem
human power expert

South Sandwich Islands
2539 Posts

Posted - 05/29/2012 :  09:28:41  Show Profile  Reply with Quote
Warren,
If Aure produced 370 W average for the hour and went 35.168 mph, that equates to a CdA of around 0.12 m2.
I'm not sure of his body weight, bike weight, tire rolling resistance, air temp, elevation..., so I say "around .12".

If I plug in 200 W, 145 lb, 32 lb bike, I get 28 mph, the same speed I managed last Oct on the dual 650C. In the last two months, I think I've been in the 180-185 W range and managing 27 mph.
I would love to put a super-strong rider on my bike to see if the extrapolation holds.

I highly recommend putting that front disc wheel on your dual 700C stickbike. I don't know how you can lay the seat back some more, though. And if I had a Bacchetta, I would run the same test. Lay the rider back as much as possible, add dual disk wheels and see what happens.

Larry Lem
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Larry Lem
human power expert

South Sandwich Islands
2539 Posts

Posted - 05/29/2012 :  09:39:19  Show Profile  Reply with Quote
When Battle Mountain is over, maybe I'll make a new fork and install a 700C front wheel. Then I can use my 700C PowerTap wheel and lay back a bit more. By now, I expected the Garmin Vector pedals to be available and could measure power on the dual 650C as is.
But I also want to try the 130 mm cranks. I shall only change one thing at a time.

I'll be running my dual 406 bike during this summer's TTs so I can use its PowerTap wheel.

Larry Lem
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n/a
deleted

2373 Posts

Posted - 05/29/2012 :  11:57:34  Show Profile  Reply with Quote
Warren,
SW winds at 26 mph when we ride today. I'll lend you a solid front disc for your 700c. I want to see what happens when we ride on Hart Rd. going south with rush hour traffic on the left. Should be no problemo 'eh?

Edited by - n/a on 05/29/2012 11:58:01
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warren
human power expert

USA
6454 Posts

Posted - 05/29/2012 :  12:35:58  Show Profile  Visit warren's Homepage  Reply with Quote
Hey Larry:

I have to build another bike to have a 700C racer with the seat laid back that far. I need to sell a couple first. I do think that horizontal position you have on your Magic Bike is key to it's speed. Because of that position it would be a racing only bike. I don't even know if I can ride in that position yet.

I do still need to try the dual disks on the highracer but as Alan notes, it's a bit windy today to try that on our weekly training ride.

-Warren.
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mhelander
recumbent enthusiast

Finland
384 Posts

Posted - 05/29/2012 :  12:53:43  Show Profile  Reply with Quote
Alan, how's your MetaPhysic project going ? Didn't you planned to have seat very much reclined, and it has big wheels...

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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alevand
human power expert

USA
3476 Posts

Posted - 05/29/2012 :  18:40:06  Show Profile  Visit alevand's Homepage  Reply with Quote
A dual 700c supine bike with the bb at seat level, The position worked for Francis Faure.

C:
Tony Levand
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n/a
deleted

2373 Posts

Posted - 05/29/2012 :  20:16:19  Show Profile  Reply with Quote
Mika,
Riding the NoCom at present to prepare for the Ohio time trial in August. That's the Big One for this season.

Will probably ride the Metabike and Cruzbike later this year.

quote:
Originally posted by mhelander

Alan, how's your MetaPhysic project going ? Didn't you planned to have seat very much reclined, and it has big wheels...

Cheers,
-Mika

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warren
human power expert

USA
6454 Posts

Posted - 08/17/2012 :  13:04:22  Show Profile  Visit warren's Homepage  Reply with Quote
I have decided to continue my project to built a 700C version of Larry Lem's "magic bike". It will have a 12" seat height and crank overlap. I still want to make it with a bent tube around the front wheel. I'd like to use 2" x .032, but that no longer exists, so I will use 2" x .049. At 1 lb per foot, it will be heavy, and very stiff.

So, the big question now is, will it bend?

I put the 2" dies into my tubing bender and spent about 30 minutes cranking the tube back and forth. Yes, it did bend, but not much, and it's not easy. I'll keep working at it, and publish pix when it starts to look like something, or becomes an expensive art project...

-Warren.
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Larry Lem
human power expert

South Sandwich Islands
2539 Posts

Posted - 08/17/2012 :  14:26:48  Show Profile  Reply with Quote
Warren,
On your 20 lb carbon fiber stickbike, even though you can't lay the seat back anymore, can you still mount disk wheels front and rear and see what happens?

Larry Lem
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warren
human power expert

USA
6454 Posts

Posted - 08/22/2012 :  08:50:11  Show Profile  Visit warren's Homepage  Reply with Quote
I now have a spiffy Zipp disk wheel I can put on the back of the CF highracer, so I will be trying that soon.

-Warren.
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warren
human power expert

USA
6454 Posts

Posted - 12/09/2012 :  06:49:27  Show Profile  Visit warren's Homepage  Reply with Quote
After several months of intermittent bending sessions, I have given up on bending the 2" x .049. tube. It has probably a 45 degree bend in it, and needs more like a 90 degree bend. I am at the point where I can spend a hour cranking the tube back and forth through the dies, and only see another 1/2" of deflection.

Does anybody know where I can get a thinner wall 2" chromo tube? The next size smaller that I can bend is 1.5", so I could try a bending 1.5" x .049" tube. I have had issues with the 1.5" x .035" wall tubes being too flexy for a monotube bike. I supposed I could always cover it in a few layers of CF it it was too flexy.

-Warren.
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harv
recumbent enthusiast

424 Posts

Posted - 12/09/2012 :  07:09:11  Show Profile  Reply with Quote
Would heating the tube with an acetylene torch help? I've seen Jesse James bend motorcycle frame tubes on TV that way.
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alevand
human power expert

USA
3476 Posts

Posted - 12/09/2012 :  08:49:53  Show Profile  Visit alevand's Homepage  Reply with Quote
Maybe aluminium 6061 2.5x.065 or 2.75x.065.

C:
Tony Levand

Edited by - alevand on 12/09/2012 08:51:04
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Speedbiker
human power expert

USA
3835 Posts

Posted - 12/09/2012 :  10:18:12  Show Profile  Reply with Quote
Warren, what radius do you seek? You can't roll a tight radius. You can get 90 degree, but the radius will be three feet! I can bend 1.75 X .049 ninety degrees all day with my Pro Tools mandrel bender. But the radius is six inches on the inside.
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warren
human power expert

USA
6454 Posts

Posted - 12/09/2012 :  11:03:50  Show Profile  Visit warren's Homepage  Reply with Quote
Harv, heating would certainly help, but the radius of the bend is about 30 inches, so it would take more heat than I can give it, and then maybe damage the bearings on the dies.

Tony, I'm sure aluminum would work, but I don't really like working with it. Maybe if I had a TIG welder...

Thom, it's about a 30 inch radius, to wrap around a 700C racing wheel.

I still have some 1.5" x 0.32" 4130 tubing left over from the chopper project. Maybe I'll just use that, and then wrap it with carbon. 3 layers should do it, and it shouldn't be too terribly heavy.

Thanks guys,

-Warren.
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Tom Schneider
recumbent enthusiast

131 Posts

Posted - 12/09/2012 :  11:22:08  Show Profile  Reply with Quote
Warren,
I have 5 ft of 2"x.035 that has been sitting since 2001 that you can have.

Tom
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warren
human power expert

USA
6454 Posts

Posted - 12/09/2012 :  12:19:30  Show Profile  Visit warren's Homepage  Reply with Quote
Woo Hoo! Thanks Tom!
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Speedbiker
human power expert

USA
3835 Posts

Posted - 12/09/2012 :  15:00:35  Show Profile  Reply with Quote
I can't see any of it working with your HF tube roller. Carbon over foam looks very tempting.....
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warren
human power expert

USA
6454 Posts

Posted - 12/09/2012 :  17:39:30  Show Profile  Visit warren's Homepage  Reply with Quote
I know the 1.5" thinwall will bend that tight as I already did it with the e-chopper. The 2" may ovalize a bit, we shall see.

Edited by - warren on 04/06/2013 18:47:40
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warren
human power expert

USA
6454 Posts

Posted - 04/06/2013 :  18:46:33  Show Profile  Visit warren's Homepage  Reply with Quote
Today was nice temperature wise, so I had no excuses for working on bikes in the garage.

Top tube is the 2" x .049" tube that I spent 3 months trying to bend. Bottom tube is the 2" x .032" tube from Tom that I spent an hour or two bending today. That's a 700C wheel. Looks like one more bending session will get it to the correct radius.



Here's a quick shot of the scale drawing of the latest design. Crank overlap, 15 degree seat, 12 inch seat height.



I now have the following parts to use with this bike:

  • XL Velokraft CF seat
  • Front / rear disk wheels
  • Steel forks for front / rear
  • Piles of bike parts from other projects



I think this should go together pretty quickly.

-Warren.

Edited by - warren on 04/06/2013 19:38:12
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