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Jerry
human power supergeek

USA
1475 Posts

Posted - 11/28/2015 :  15:18:10  Show Profile  Reply with Quote
At least you are getting to work on your bike. I have been gone for over 3 1/2 weeks. Now it is winter in Texas. Going home tomorrow. Hope you get it the way you want soon.
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alevand
human power expert

USA
3541 Posts

Posted - 11/28/2015 :  17:21:06  Show Profile  Visit alevand's Homepage  Reply with Quote
I moved the truss supports back, and aligned it. Steering is still a bit heavy with some flop for going slow up mountains at 4 mph, but better. Flop is almost neutral at steering locks. I can do circles on a two lane road, almost with no hands. I can live with it. Toes are still hitting, so need to move that and finish weld it up. Started work on new steering, linkage, and narrower bars using tt brake handles. Using a 1 or 1 1/8 tube near plumb support and two shouldered ball bearings at the top. Aluminum 1 x .035 brace tube up to the front pop riveted. Seat needs some attention too. Forgoing fox hunting tonight to work on bike. If I can get all this done tomorrow then I can concentrate on mechanicals, electrical, stowage and fairing. Less than 4 weeks to go.

C:
Tony Levand

Edited by - alevand on 11/28/2015 17:23:44
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alevand
human power expert

USA
3541 Posts

Posted - 11/29/2015 :  05:22:51  Show Profile  Visit alevand's Homepage  Reply with Quote
https://youtu.be/Fm1ZgXVCHJ8

A little too narrow after I bent them downward, thumb interferes with bearing and clamp. I may reverse it, have the outside stationary with support welded to it and the 3/4 tube rotate, welded the bars to the top of the tube at zero tiller. I flared the end of the brake handles.

C:
Tony Levand

Edited by - alevand on 11/29/2015 05:27:19
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alevand
human power expert

USA
3541 Posts

Posted - 12/01/2015 :  04:41:37  Show Profile  Visit alevand's Homepage  Reply with Quote
I test rode it Sunday for 40 miles on the new Cal Sag trail. Steering is a little heavy for negotiating the dirt trail behind my house, but on the road above 15 or 20 mph its fine, above 30 mph it seems a noodley, due to the flex in the steering and front end with the amount of force needed to steer. Rides over bumps great, though. Without the 15 lb fairing the bike feels light and nimble and climbs in a higher gear. It seems to corner better on the curvy trail, but it may be because my speeds are lower. I want to move the wheel attachment forward 1/2 inch. This will reduce trail 2 inches and put in the middle if what it had with the arms and present.

C:
Tony Levand
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alevand
human power expert

USA
3541 Posts

Posted - 12/04/2015 :  14:43:22  Show Profile  Visit alevand's Homepage  Reply with Quote
Fork snapped when I tried to bend it. I made a new one from an old cr-mo 26 inch mountain fork: Test ride tomorrow. I should have put a small piece of inner tube over the ball joint.




Note the improved angular motion of the ball joint, modified with a round file.

I wire brushed the fork and sprayed it with acrylic clear coat.

I am coining the phrase "SIMPLEX STEERING" for this set up ad opposed to OECs full "DUPLEX STEERING" patented in 1927. Simplex because it only had one virtual pivot and one fixed pivot where Duplex has two virtual pivots, one top one bottom.


... I added a boot around the ball joint and a fender.

I am thinking od a remote kick stand. I am thinking of making it curved , so it travels in an arc.That way it hugs the seat support and leaves room for cargo.

Test riding the new fork today after lunch.
C:
Tony Levand

Edited by - alevand on 12/06/2015 06:27:02
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alevand
human power expert

USA
3541 Posts

Posted - 12/06/2015 :  06:15:52  Show Profile  Visit alevand's Homepage  Reply with Quote
Yesterday after a 10 mile test ride, I cut the frame on the bottom at the joint just in front of the chain wheel and rewedded it. This raised the BB 2 inches and reduced the trail. Before the steering was too heavy for the decent down the 90% grade grassy hill to the path on the berm between the ponds. Steering is much lighter and slow speed excursions from the intended path considerably less. Seat is an inch higher too, from 8 to 9 mesh bottom to road surface. Originally I had 11 to the seat tube or 10 from the mesh before I changed the front end. The only thing I would change is to put the brakes on the back of the fork. They were welded on several years ago for the winter commuter bike. I think it is satisfactory for a tour. I am now going to concentrate on the new remote steering setup. The front end has taken much longer than anticipated, I hope I can get it together in time for the ride.


... Well I decided that I don't have time to redo the steering. I am using the old asymmetric one, it's off to one side to make room for the linkage arm and knees. But I moved the linkage to the top, thusly it could be centered. I made a new linkage bar and strut from 5/8 x .028 tube and ran the brake cable on it. Ran out of .028 wire and almost out of gas. The .035 wire started sticking and made an ugly weld. Time for lunch then a test ride...

Didn't got out for a ride until 3 pm, got 27 miles in. Steering is good, no hands at 36 mph.

C:
Tony Levand

Edited by - alevand on 12/06/2015 16:56:58
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warren
human power expert

USA
6470 Posts

Posted - 12/06/2015 :  18:13:14  Show Profile  Visit warren's Homepage  Reply with Quote
Wow, sounds like the tweaking paid off! Are you happy with the handling and brake steer now?
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Jerry
human power supergeek

USA
1475 Posts

Posted - 12/06/2015 :  18:29:41  Show Profile  Reply with Quote
90% grade hill is pretty steep! lol Glad you are getting it going your way. I like the coro fender the guy on CGOAB posted.

quote:
Originally posted by alevand

Yesterday after a 10 mile test ride, I cut the frame on the bottom at the joint just in front of the chain wheel and rewedded it. This raised the BB 2 inches and reduced the trail. Before the steering was too heavy for the decent down the 90% grade grassy hill to the path on the berm between the ponds. Steering is much lighter and slow speed excursions from the intended path considerably less. Seat is an inch higher too, from 8 to 9 mesh bottom to road surface. Originally I had 11 to the seat tube or 10 from the mesh before I changed the front end. The only thing I would change is to put the brakes on the back of the fork. They were welded on several years ago for the winter commuter bike. I think it is satisfactory for a tour. I am now going to concentrate on the new remote steering setup. The front end has taken much longer than anticipated, I hope I can get it together in time for the ride.


... Well I decided that I don't have time to redo the steering. I am using the old asymmetric one, it's off to one side to make room for the linkage arm and knees. But I moved the linkage to the top, thusly it could be centered. I made a new linkage bar and strut from 5/8 x .028 tube and ran the brake cable on it. Ran out of .028 wire and almost out of gas. The .035 wire started sticking and made an ugly weld. Time for lunch then a test ride...

Didn't got out for a ride until 3 pm, got 27 miles in. Steering is good, no hands at 36 mph.

C:
Tony Levand

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alevand
human power expert

USA
3541 Posts

Posted - 12/07/2015 :  06:15:44  Show Profile  Visit alevand's Homepage  Reply with Quote
Yes, its seems OK. The strut really stiffened up the system.

Yes, short but steep.

I want to mount the generator and kick stand, move the seat a little forward, clean and oil the chain, replace the front derailleur cable before starting to think about the fairing. Everything seems to take so much time.


quote:
Originally posted by warren

Wow, sounds like the tweaking paid off! Are you happy with the handling and brake steer now?



C:
Tony Levand

Edited by - alevand on 12/07/2015 06:18:47
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alevand
human power expert

USA
3541 Posts

Posted - 12/08/2015 :  18:36:07  Show Profile  Visit alevand's Homepage  Reply with Quote
2015-12-07 Mounted generator tonight after 2 tries

2015-12-08 Changed front dérailleur cable, welded in 2 noodles, eliminating the cable housing. Much cleaner looking. Removed miscellaneous extraneous stuff. Moved seat 1/2 inch forward, welded a rotation stop. I think I can use a 1/4 hollow fiberglass rod (Big Lots tomato stick) for the kickstand (now prop) from the bottom of the seat to ground. Need to find a way to stick it down and have it hold in place. Need a parking brake, small bungee on brake handle to keep it from rolling with the prop in place. That should be enough remind me to raise the prop when starting out. Not having the remote actuated retractable landing gear frees up stowage space under the seat.

C:
Tony Levand

Edited by - alevand on 12/08/2015 18:52:34
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warren
human power expert

USA
6470 Posts

Posted - 12/08/2015 :  19:13:33  Show Profile  Visit warren's Homepage  Reply with Quote
Sounds like you are making good progress. Are you still planning on a big ride south this month?
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Jerry
human power supergeek

USA
1475 Posts

Posted - 12/09/2015 :  03:16:35  Show Profile  Reply with Quote
I cut up old inner tubes for the brakes. I make them 1/2"-3/4" wide. I carry extras with me.
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alevand
human power expert

USA
3541 Posts

Posted - 12/09/2015 :  08:05:29  Show Profile  Visit alevand's Homepage  Reply with Quote
Hi Warren, Yes, going south. Might meet up with Jerry.

Thanks Jerry, Ive got plenty of old tubes around.

Massaged front derailleur this morning, shifts fine now..
Back brake cable sticky in noodle, lining is protruding.
Clean and oil chain
Is that it? I can start on the coro body work soon, only two weekends to go...

https://www.crazyguyonabike.com/doc/?o=tS&doc_id=17079&v=1W

quote:
Originally posted by warren

Sounds like you are making good progress. Are you still planning on a big ride south this month?



C:
Tony Levand

Edited by - alevand on 12/09/2015 08:10:57
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alevand
human power expert

USA
3541 Posts

Posted - 12/11/2015 :  12:39:04  Show Profile  Visit alevand's Homepage  Reply with Quote
Cleaned and oiled the chain, adjusted the rear dérailleur, wasn't shifting to top gear. Welded in noodle for the rear brake, rerouted the cable and installed new v-brakes with a twisty noodle holder. The old v-brake was worn out, all the way though the bushing.

I will test ride this afternoon. Had to work til midnight Wednesday, so I took the afternoon off.

I had the chain twisted inside the chain tube,.. why is the chain at an angle? Doe!

...Test rode 42 miles in the dark using the LED generator light, works great on the bike trail.

2012-12-12... Decided to try to fit the old fairing back on. Shooting for a test ride this afternoon.

... Well progress has been slow. The front of the bike is higher and I cant see over the fairing...no test ride today...

C:
Tony Levand

Edited by - alevand on 12/12/2015 16:18:37
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warren
human power expert

USA
6470 Posts

Posted - 12/13/2015 :  06:36:21  Show Profile  Visit warren's Homepage  Reply with Quote
Ah, you moved the BB up a couple inches. I did not realize that bike had a 10 inch seat, that is pretty low. How are you going to change the fairing so you can see over your feet? You need to see the road to avoid the pot holes and wood chucks.
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alevand
human power expert

USA
3541 Posts

Posted - 12/13/2015 :  11:21:37  Show Profile  Visit alevand's Homepage  Reply with Quote
2015-12-13
Putting on the old fairing, it was too high in the front to see. Today I bent the bars down lower, painted them blue, borrowed Warren's idea and used inner tubes as grips. I ground down the cable end of the hand brake bracket, replaced the adjustable locknut with a washer. This made enough clearance to be able to lower the fairing and inch and also narrow it 2 inches. Test rode around the block today with fairing partially strapped on, windy out. Much too much trial in the front end for side gusting, difficult and heavy to control, may be better without the giant ram air scoop open front.


https://www.crazyguyonabike.com/pics/docs/00/01/70/79/large/KIMG0060.JPG?v=0



C:
Tony Levand
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alevand
human power expert

USA
3541 Posts

Posted - 12/13/2015 :  13:53:38  Show Profile  Visit alevand's Homepage  Reply with Quote
Comparing a normal fork to simplex fork. Not a true comparison, if the steering angle on the on the motobecane was the same, then it would be 50 degrees or so.



C:
Tony Levand

Edited by - alevand on 12/13/2015 13:54:03
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alevand
human power expert

USA
3541 Posts

Posted - 12/14/2015 :  04:14:59  Show Profile  Visit alevand's Homepage  Reply with Quote
CONCLUSION:

A virtual pivot steering system was tried on a long wheel base recumbent bicycle with a 10 inch seat hight and 80 inch wheel base. The system allows a unobstructed view over the front 700c tire. The virtual pivot steering axis is defined by a ball joint pivot above the tire and two linkages connected lower on the fork, the two linkages form a 4-bar linkage. The virtual pivot steering axis is defined by the upper ball joint and the intersection of the line of action of the two links. Since the bike was to be ridden on the street, a large steering angle was needed, 90 degrees lock to lock. This required that the links be mounted high on the fork for tire clearance, approximately 7 inches down from the ball joint. The reaction forces on the links was 4 times the force on the tire contact patch. When the steering is turned the virtual pivot moves from center over to one side, this causes a moment about the steering axis from any force applied to the contact patch, thus braking causes a positive torque, not unlike having negative caster. To counteract this brake steer, a large amount of positive caster is needed. In this case 10 to 12 inches was used. Near the steering lock, at low speeds the wheel flop and reaction forces in the links balance and very little steering effort is needed and tight circles can be easily ridden with a radius of two wheel bases. The bike was ridden 200 miles and the steering was found to be very stable at 36 mph and over bumps and rough terrain. It could be ridden with no hands. Cornering was good. Due to the large amount of trail, weight on the bike needed to be well balanced for it to track true. The system works quit nicely for an unfaired or tail faired bike. Slow speed steering is a little heavy. However when a full fairing was tried on a windy day, side loading from gusts combined with the large amount of trail produced very large steering torques which where difficult slow slow recover from. It was therefore decided that virtual pivot system was inappropriate for a full faired street bike.


C:
Tony Levand

Edited by - alevand on 12/14/2015 04:18:02
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Jerry
human power supergeek

USA
1475 Posts

Posted - 12/14/2015 :  05:00:27  Show Profile  Reply with Quote
Too bad it didn't work out. Are you going back to remote steering using a smaller wheel? I am about to put remote steering on my LWB, and plan on using a 20" wheel with a wider tire.
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alevand
human power expert

USA
3541 Posts

Posted - 12/14/2015 :  06:38:34  Show Profile  Visit alevand's Homepage  Reply with Quote
i am going out at lunch to get more shielding gas. Jerry, should I disconnect the regulator after each use or just turn off the valve. This last tank didn't seem to last much.

I really like how the big wheel rolls, it will be great on chip seal.

The steering rod is too high to fit in the front of the fairing.

C:
Tony Levand

Edited by - alevand on 12/14/2015 06:45:14
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Jerry
human power supergeek

USA
1475 Posts

Posted - 12/14/2015 :  09:53:52  Show Profile  Reply with Quote
No need to disconnect them Tony. Just turn the valve off on the cylinder and make sure the valve on the regulator is off also. Sometimes when it is left under pressure it can cause damage to the regulator. I always drained the gas each time to relieve the pressure. You can do it easily if you have a purge button.

I would like to have a bigger wheel also, just don't want to build or buy a new front fork. So, I us either a 32mm or 35mm 20" tire.

Hope you get it worked out.

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alevand
human power expert

USA
3541 Posts

Posted - 12/14/2015 :  10:43:39  Show Profile  Visit alevand's Homepage  Reply with Quote
I had a 451 by 1 1/8 on it (28mm).

I traded in my 2 40 cu ft bottles for a 125 cu ft bottle.
C:
Tony Levand

Edited by - alevand on 12/14/2015 10:46:28
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aarntate
Starting Member

New Zealand
7 Posts

Posted - 12/14/2015 :  12:44:33  Show Profile  Reply with Quote
Your conclusion is interesting. I think you might come to a different conclusion if your "head angle" was close to vertical, and the effective trail was reduced.
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Speedy
recumbent guru

USA
909 Posts

Posted - 12/14/2015 :  12:44:42  Show Profile  Reply with Quote
not sure if it applies here ...
high pressure gas cylinders have double seated valves
one seat on the bottom to close
one seat on the top to seal the valve stem
when the valve is opened it should be opened all the way to the upper seat so the gas won't leak around the stem and drain the contents

low pressure cylinders like CO2 or acetylene are opened only one quarter to one half turn

Steve Delaire

http://molten3d.blogspot.com
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Jerry
human power supergeek

USA
1475 Posts

Posted - 12/14/2015 :  13:06:46  Show Profile  Reply with Quote
You will save time and money with the larger bottle.

How about a 24" or 26"-559? If I remember right, a 559 is about 1" shorter than a 650.
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