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warren
human power expert

4269 Posts
Posted - 10/23/2011 :  07:39:28  Show Profile  Visit warren's Homepage  Reply with Quote
Hi Thom,

Yes, Human/electric power. I don't remember the picture of your bike. Can you post a link, or send me the pic? How is the handling with a more relaxed head tube? I have a pretty beefy front suspension unit, so I would feel safe with up to about 4" of trail. This bike will need be be able to go fast.

This is a big bike. Here's mostly to scale me on the bike. In reality I would probably be slouched forward a bit so the bars would not need to be that long. Also probably they will be lower.



Here's me on a choppersus.com frame that is a bit small for me.



-Warren.
Edited by - warren on 10/23/2011 07:44:25
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alevand
human power supergeek

USA
1651 Posts
Posted - 10/26/2011 :  14:27:21  Show Profile  Visit alevand's Homepage  Reply with Quote
Looks like the pedal hits the front tire when turning and pedaling.

C:
Tony Levand
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warren
human power expert

4269 Posts
Posted - 10/26/2011 :  16:03:54  Show Profile  Visit warren's Homepage  Reply with Quote
No pedal to tire interference, but maybe some foot to tire action.
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warren
human power expert

4269 Posts
Posted - 10/31/2011 :  10:27:42  Show Profile  Visit warren's Homepage  Reply with Quote
I finally broke down and bought a tubing roller from Harbor Freight tools. It seems relatively well made. I also bought the stand. It's a little wobbly, and yes it would work best if bolted to the floor, but I am going to bolt it to some 2x4s to spread out the load instead.
It has dies for 1/2", 1", 1.5" and 2". I am planning on building this bike using 1.5" tubing, so that works for me.



Here is a short section of 1.5" x .035" 4130 tubing that I rolled. 6" of tubing on each end will be lost. The section in the center is the minimum radius bend that I will need for this bike, so I guess this will work for me. It takes a lot of muscle power to roll the tube back and forth, but that's ok I need the exercise. The tube had a small groove in it at this large angle but otherwise the bend looks great.



Next steps are to make a full sized drawing and order some tubing.
-Warren.
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warren
human power expert

4269 Posts
Posted - 11/02/2011 :  09:20:03  Show Profile  Visit warren's Homepage  Reply with Quote
I ordered 25 feet of 1.5" x .035 wall 4130 steel tubing from Aircraft Spruce.

I called Dillsburg first and talked to a nice but very old sounding man. I guess that explains why he doesn't sell via the Interweb. He said his prices were cheapest but were $1.50 / foot higher than Aircraft spruce. PLUS I would have had to buy in 18.5 foot sections that he would cut into UPS ship-able lengths. He was confident he had the lowest prices and couldn't understand why I would want to check elsewhere first.

-Warren.
Edited by - warren on 11/02/2011 09:21:40
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Larry Lem
human power supergeek

South Sandwich Islands
1997 Posts
Posted - 11/02/2011 :  09:24:24  Show Profile  Reply with Quote
Is Aircraft Spruce shipping you a continuous, 25 foot long piece of tubing, or are they cutting it into sections?

Larry Lem
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warren
human power expert

4269 Posts
Posted - 11/03/2011 :  17:06:37  Show Profile  Visit warren's Homepage  Reply with Quote
They can ship up to 8ft lengths. I chose 5 - 5 ft chunks.
They arrived today.
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warren
human power expert

4269 Posts
Posted - 11/06/2011 :  14:15:35  Show Profile  Visit warren's Homepage  Reply with Quote
I finished the full sized drawing and started rolling tubing. The drawing isn't high enough contrast on the brown paper to show up on the camera, so you can't see that the final drawing is just a bit different than the last drawing above.



The tubes have turned out perfect so far, except for the bottom tube with the compound curve does have a couple artifacts where the bend transitions. It only takes about 20 minutes to bend each tube.

-Warren.
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Speedbiker
human power expert

USA
2037 Posts
Posted - 11/06/2011 :  15:54:50  Show Profile  Reply with Quote
Looking good so far, Warren.
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warren
human power expert

4269 Posts
Posted - 11/16/2011 :  07:34:39  Show Profile  Visit warren's Homepage  Reply with Quote
I finished bending the main frame tubes and am now waiting on the head tube and BB. The image below shows the tubes laid out on the full size drawing. I photoshopped out the ends of the tubes to get a better idea of when it will actually look like.



I'm thinking about adding a rear suspension. Originally I had decided not to use a rear suspension as every variation I tried looked funky or took up too much room. I think this one works.



-Warren.
Edited by - warren on 11/16/2011 07:46:21
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Speedbiker
human power expert

USA
2037 Posts
Posted - 11/16/2011 :  08:24:37  Show Profile  Reply with Quote
Won't that pogo? Doesn't look like the chain will pass thru the theoretical point of pivot. And, where are the ape hangers(armpit dryers)?
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warren
human power expert

4269 Posts
Posted - 11/16/2011 :  08:43:04  Show Profile  Visit warren's Homepage  Reply with Quote
It may pogo, but this bike is not meant to be practical or particularly efficient. It will use some type of e-assist for the go-fast part of the riding.

Ape hanger handlebars? Like on a Tour-Easy? I agree that those would fit the aesthetic of this bike, but I have not decided on the handlebars yet. I will have to see what feels comfortable to reach. I was thinking of something minimalist like board racer bars, but I may have to be very hunched over to reach those and that does not sound comfortable to me. This bike does not need to be a speed-racer, but because I am a recumbent head it does need to be comfortable. Speaking of that, I did order a big-a$$ bike seat.

-Warren.
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Speedbiker
human power expert

USA
2037 Posts
Posted - 11/16/2011 :  16:44:06  Show Profile  Reply with Quote
I had an exercise bike seat on one I built. It was pretty nice. My chopper has stringray bike ape hangers. I suspect you'll end up with the "not super wide" beacon bars. Apes would be cool, though.
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warren
human power expert

4269 Posts
Posted - 11/20/2011 :  16:31:49  Show Profile  Visit warren's Homepage  Reply with Quote
I received the head tube and bottom bracket and spent some time putting the main frame together. I started with attaching the head down tube to the head tube and worked from there.

Here's the tubing notcher I used to fish mouth the tubes.



I used my homemade frame jig to align each tube while I tack brazed it and it turned out pretty well. The fork is just hanging on the frame in this picture.



Wow, that one section of straight tube is really conspicuous. Don't worry, I will be attaching a seat and suspension spring and stuff to it so it will be somewhat disguised. Next step is to build the rear stays and the suspension pivot.

-Warren.
Edited by - warren on 11/20/2011 16:35:30
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Speedbiker
human power expert

USA
2037 Posts
Posted - 11/20/2011 :  19:10:07  Show Profile  Reply with Quote
Braze? You are old skool!
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E.B. Erickson
Starting Member

47 Posts
Posted - 11/21/2011 :  03:29:34  Show Profile  Reply with Quote
So are you going to Steampunk that design? With those curves, it's just crying for brass lanterns, etc...
--ElJay
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warren
human power expert

4269 Posts
Posted - 11/21/2011 :  06:27:46  Show Profile  Visit warren's Homepage  Reply with Quote
Thom - I'd love to use a TIG welder, just can't afford it now. Gas is (relatively) cheap.

Eljay - no frufru brass bits for me. I'm going for the super-clean look and will be hiding all the cable and wires in the frame.

I may do some gussets though. These are cool:


https://www.nolimitparts.com/prodinfo.asp?number=SW-6
http://www.tmrcustoms.com/store/index.php?main_page=product_info&cPath=3_30&products_id=408

This will have an electric motor but I haven't decided whether I should just use the hub motor from my commuter MTB, or go completely crazy with a big new non-hub motor mounted in the frame.

-Warren.
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Speedbiker
human power expert

USA
2037 Posts
Posted - 11/21/2011 :  07:31:35  Show Profile  Reply with Quote
I've been MIG welding cromoly with mild steel wire for years, with zero failures.

Several posts back I meant "not super wide BEACH bars".

Keep up the nice work.
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warren
human power expert

4269 Posts
Posted - 11/23/2011 :  11:03:48  Show Profile  Visit warren's Homepage  Reply with Quote
I mounted the front suspension fork last night. This is a nice fork that I picked up in a fleabay auction, but it was made before MTB disk brakes were standardized. It does have disk brake mounting tabs but I'll need to make an adapter to be able to mount a standard disk brake. In addition, the disk brake on my current disk brake front wheel barely clears the fork tube, and the brake rotor mounting bolts have hard interference. The only option I can think of it to machine several millimeters off of the disk rotor mount on the hub. Does anyone have any other ideas or know of a hub that would work better?

Thanks,

-Warren.
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Speedy
recumbent guru

USA
661 Posts
Posted - 11/23/2011 :  12:05:54  Show Profile  Reply with Quote
counter sink the disk and flat head bolts
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Rick G
Starting Member

34 Posts
Posted - 11/23/2011 :  14:26:34  Show Profile  Reply with Quote
Warren how about a sturmey-archer XFD hub brake. It would look good on the bike.

Rick Gritters
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warren
human power expert

4269 Posts
Posted - 11/23/2011 :  14:44:20  Show Profile  Visit warren's Homepage  Reply with Quote
Good idea Steve. I'll look to see if there is clearance for even that.

Rick - how is the stopping power on those brakes? It has to be able to stop a heavy (70 or so pounds with motor and battery) bike rapidly so I am not squashed like a bug when someone pulls out in front of me while I am doing my easy rider impression at 30 MPH.

Thanks,

-Warren.
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warren
human power expert

4269 Posts
Posted - 11/23/2011 :  17:34:30  Show Profile  Visit warren's Homepage  Reply with Quote
Looks like that drum brake has good stopping power and should work well. Thanks Rick.

Here's the front fork mounted in the frame.



Those handlebars look cool but they would be a reach.

-Warren.
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Speedbiker
human power expert

USA
2037 Posts
Posted - 11/23/2011 :  21:17:07  Show Profile  Reply with Quote
It will look right at home on Chicago's new board track. Though, they might not approve....
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Rick G
Starting Member

34 Posts
Posted - 11/24/2011 :  06:03:14  Show Profile  Reply with Quote
The Sturmey should have plenty of braking action, depending on what you use for levers. There is also a little breakin period to bring them to optimum. You might also consider using their geared 8 speed with integral drum brake for the rear. That would keep the clean look and simplify the rear end. I've been running one on my FWD bike for over 10,000 miles including the ride across the US and it has worked well. It even comes with a twist grip throtle, eer shifter.

Rick Gritters
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