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Comparing strengths of alternative hinges, Qix, Visc, Birdy, IVE, Spin

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Comparing strengths of alternative hinges, Qix, Visc, Birdy, IVE, Spin

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Old 12-19-17, 06:38 AM
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tomtomtom123
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Comparing strengths of alternative hinges, Qix, Visc, Birdy, IVE, Spin

I'm looking for a bike with an alternative hinge design to the standard sideways swing hinge, due to past experience with damage to this type of hinge, possibly due to transport or airplane travel.
  • Something that can be used for loaded touring up to a total of 100kg including rider and cargo,
  • stock cost less than $1000,
  • can be easily broken down to fit in non-oversize luggage using small tools at hand,
  • either in 1 or 2 suitcases with enough space for adding adequate padding and accounting for external compression,
  • ideally separating the hinge and frame into 2 separate pieces,
  • and has standard dropouts and free hubs to fit 9/10 speed cassettes.


Any ideas?

I've been reading about the Qix, Visc, Birdy, IVE, Spin. Some of these bikes are in shops a 6 hour train ride away, while others can only be purchased over the internet, so I can't easily go take a look at them.

Qix: the vertically folding hinge has some benefits over the sideways swing hinge, in that the horizontal pin at the bottom of the hinge would be symmetrically loaded, and the direction of fold is the same as the rolling direction. But when folded and laid down sideways like in a suitcase during transport, sideways compression may twist the hinge. One doubt I have is that the pin appears much smaller in diameter than what's used in sideways hinges. The internal latch at the top of the hinge helps resist some of the twisting / torsion of the frame, but I think the horizontal pin will experience more torsion than in the standard sideways swing hinge.
  • Can the hinge be separated for packing in suitcase for flight?
  • If the pin and shaft start to wear and become loose, how do you tighten it?
  • Does anyone know the OLD dropout width and axle diameter? 406?
  • Would it be possible to fit my old 20" wheel with 135mm wide SRAM dual drive (not sure about axle width)?

Visc D18: It has a floating miniature top tube above a standard sideways swing hinge. This small tube I think helps strengthen the hinge by increasing the overall height of the system, and unloads some of the internal compression from the main lower hinge.
  • How effective is this?
  • Does anyone know the OLD dropout width?
  • I saw on the Nomadic Inc website, they have modified the hinge so that the pin can be removed. Is it easily done by myself?
    https://nomadic.net/shop/folding-bik...ppletini-green
  • How is he able to fit the rear frame with the wheel still attached into a suitcase? I measured from the photo that it needs a suitcase 80cm long, while most large suitcases only go up to 72cm internally, and doesn't leave much space for padding.
  • Over time, would the pin start to deform, making it no longer possible to remove?
  • I've read that the rim width is narrow on this bike and some people had problems fitting wider tires? Is it 406?
  • I would be interested in the 16" SL version, but don't want the special Shimano Capreo hub.


Birdy and IVE: The fold under design of the rear part of the frame leaves the main top tube intact. The pin connections where the chainstay meets the BB and the seatstay meets the seat tube don't experience much vertical bending, mostly sheer stress. Although I wonder about torsion.

The problem with the Birdy for me is the price, requires the R&M rear folding rack that's made for it which can only carry 15kg and sits quite high, and is more likey to be stolen locally. The older V-brake version which they renamed World Birdy seems to not be in production anymore, and they're moving to all disc brake. The distance between the folding pivot to the BB requires a chain hook for folding, which is ok but might accidentally get bent.

The problem with the IVE is that the max weight is 85kg including cargo and add on parts. Is this because of the 120mm OLD and dishing? This doesn't allow for carrying more cargo for longer tours.

Spin: Can be completely broken down into straight and flat pieces, can be packed very tightly into a suitcase, using 5, 6, 8, 10mm hex wrenches. But the chainstay goes straight across to the seatpost and BB, without a seatstay or other bracing, which means there is a lot of bending moment on the chainstay. The FSIR brand is disappearing, and shops that used to carry them no longer do.
  • What are your thoughts on the strength of the "cantilevered" chainstay for loaded touring?

Giatex: The telescoping top tube means there is no folding or rotating hinge. The 2 parts of the frame can be easily pulled apart. However the fork seems to be using a threaded stem, and you would need to carry large wrenches for reassembly. The 16" version can fit in a suitcase with the front wheel removed, with the fork still attached, but the 20" version has a much longer top tube and requires the fork to be removed so that the top tube can be placed diagonally into the suitcase. It requires a low rack that can slide under the top tube when telescoping, Tern Cargo Rack probably fits. It would have to be imported from Taiwan, and specifications aren't easily found. I assume the 6 speed free hub would have to be changed to fit a 10 speed cassette.









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Old 12-19-17, 08:55 AM
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Comparing strengths of alternative hinges ...

Really? You get Data.. Its called Destructive Testing ,, you get samples *, and the testing lab tries to break it, with equipment that has data recording equipment .

That records the amount of force it took to break it... that peaks at the point it failed..

*you have to buy one of each, Go...





...

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Old 12-19-17, 09:06 AM
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Originally Posted by fietsbob View Post
Really? You get Data.. Its called Destructive Testing ,, you get samples *, and the testing lab tries to break it, with equipment that has data recording equipment .

That records the amount of force it took to break it... that peaks at the point it failed..

*you have to buy one of each, Go...



...
What about doing Finite Element Analysis with computers? No breaking things.

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Old 12-19-17, 09:21 AM
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Of course, Here you just get competing opinions,
try a University Engineering post grad study..?

you might be asked to fund it, for it to happen..






..

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Old 12-19-17, 10:39 AM
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Originally Posted by mtb_addict View Post
What about doing Finite Element Analysis with computers? No breaking things.
FEM is only as good as the input data that's used. No matter how accurate the model is.

Any good FEM analysis is eventually verified with real world testing. Unless of course they have already collected enough case studies of various permutations of variations to cross reference from. So you still need to break stuff along the way before you get to pure virtual simulation. That's just how it works in the real world.
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Old 12-19-17, 11:10 AM
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why not buy a bike that doesn't have a hinge, like a bike friday? folds and fits in a suitcase. standard parts.
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Old 12-19-17, 11:12 AM
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I have no experience with the bikes listed but would avoid the Giatex. That tiny bolt frame clamp seems small. I think long term the smaller front tube would ovalize the red rear tube.
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Old 12-19-17, 11:23 AM
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Originally Posted by maxxevv View Post
FEM is only as good as the input data that's used. No matter how accurate the model is.

Any good FEM analysis is eventually verified with real world testing. Unless of course they have already collected enough case studies of various permutations of variations to cross reference from. So you still need to break stuff along the way before you get to pure virtual simulation. That's just how it works in the real world.

correct and you better break 10 or more to get reliable data.


Despite the cool idea to take the visc frame apart , the warranty is lost if you do that. Its much easier to take the rear wheel off.
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Old 12-19-17, 12:54 PM
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I think instead of asking if these models are tough enough for touring/packing;
a better question should be "I'm going bike touring; which bikes have proven to
be tough enough for the task?".

I notice most folks that go touring; and need a bike that folds - go with Bike Friday.
BFold in NYC sells a discontinued model that may fit all your requirements - Companion.
bfold.com

"I'm looking for a bike with an alternative hinge design to the standard sideways swing hinge,
due to past experience with damage to this type of hinge, possibly due to transport or airplane travel.

Something that can be used for loaded touring up to a total of 100kg including rider and cargo, Yes.
stock cost less than $1000, Yes.
can be easily broken down to fit in non-oversize luggage using small tools at hand, Yes.
either in 1 or 2 suitcases with enough space for adding adequate padding and accounting for external compression, 1 case.
ideally separating the hinge and frame into 2 separate pieces, Yes, on some models.
and has standard dropouts and free hubs to fit 9/10 speed cassettes." Yes.
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Old 12-19-17, 12:54 PM
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Originally Posted by ttakata73 View Post
I have no experience with the bikes listed but would avoid the Giatex. That tiny bolt frame clamp seems small. I think long term the smaller front tube would ovalize the red rear tube.
There are 2 knobs at the bottom of each end of the rear frame, but I don't know what's at the other end of the knob. They force up the silver inner tube against the top of the outer red tube. They are 6 sided. The top side of the inner tube has notches / tabs. On the top ends of the red outer tube there are these black dots, and I suspect underneath is a plastic sleeve that fits into those notches. because the top of the tubes are a V shape, the top is held in place, but there is probably some play at the bottom. The durability of pressing the weight on those 2 knobs depends on what's on the end of the knobs. The front knob probably doesn't experience much force because the direction of "rotation" when loading the bike, but the rear knob probably experiences a lot of compression. It would have made more sense to have the rear knob on top.

In the image below, you can see the socket head safety screw that prevents the rear frame from sliding off. If you remove the screw, you could pull the 2 frames apart. Removing the wheels and reversing the rear frame 180 degrees horizontally, you could slide the rear frame all the way forward and slip the front fork in between the rear frame for packing.




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Old 12-19-17, 02:10 PM
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Originally Posted by 1nterceptor View Post
ideally separating the hinge and frame into 2 separate pieces, Yes, on some models.
I see there is a discontinued model called the Pocket Companion OSATA that has a telescoping top tube that can be pulled apart.


The later models both fold and have the adjustable top tube.

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Old 12-19-17, 03:11 PM
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oh I am thinking to myself ..... please do whatever it takes to actually ride these ... before you spend that kind of coin on something wild ......
I can tell you that it is very easy to take a wheel off the bike and than pack it in a standard legal suitcase.
Its not easy, even impossible, to change the ride of the bike ...
Just figure the 2 minutes extra to take wheel off versus the hours you ride the bike
( well on some of your examples, you wont ride for hours ...only once ..lol )


thor
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Old 12-19-17, 03:18 PM
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Originally Posted by tomtomtom123 View Post
I see there is a discontinued model called the Pocket Companion OSATA that has a telescoping top tube that can be pulled apart.
Yes, that's exactly what I was referring to that might work for you. BF made
Companions that had solid main frames; as well as ones that split.
I believe BFold has both models. As well as other BF's; PakiT, NWT, Tikit, etc.
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Old 12-19-17, 03:28 PM
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Well yea, look at CGOAB, you find lots of touring journals , folding section has lots of bike friday owner-writers ..
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Old 12-19-17, 03:40 PM
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The problem for me is that there aren't shops near me that have these models. The closest Dahon dealer for the Qix is a 5-6 hour train ride away. The Visc is 10 hours away. Bikefriday would have to fly across the ocean. There are some BF dealers in neighboring countries, but I don't think they would have the discontinued PC on demo.

I'm browsing videos and images of the frames, and superimposing them on an image of my current bike to measure the dimensions and seat / handlebar positions, by scaling the images to match the tires and wheelbase.

It's really difficult to find detailed photos and demos of the BF bikes on the internet, and their website hasn't really changed since the last time I looked at it 7 years ago, with lots of broken links and redirects.
  • After folding the rear wheel on the PC, how does it stay put if you lift the bike? Or will it drop down?
  • How do you roll the PC bike when folded? (especially with a fender or rack)
  • The BF "folding" rack doesn't actually fold when on the bike?
    It appears to only fold after you remove it from the bike. it's also extremely tall. Videos of people folding the bike with the rack has the entire bike off the ground, resting on the rack. A lot of that weight is bending the unhinged seat stay. A different rack would probably work better for folding the bike.
  • When folded without the rack, what is the bike sitting on when resting on the ground? Photos show it resting on the unhinged seat stay. Risk of bending it?



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Old 12-19-17, 04:07 PM
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Bike Friday makes up for its lack of dealers by connecting existing owners with prospective owners for test rides. If you call them (800#) or email them, they can see if anyone near you owns a BF. That's how I test rode the pakiT before I bought it. Perhaps fewer owners where you live but worth a phone call to find out. The New World Tourist and Pocket companions will ride pretty much the same, geometry is identical.
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Old 12-19-17, 06:14 PM
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Not disclosing your location important to you, Why? [Witness Protection relocation is a good reason]

Do you have any bike? do you have a tape measure? does that bike feel OK? measure it.


Bike Friday is the Only one with several frame (Length) sizes , all the others just make one..

Brompton's just make one.. But they have bar mast.handle bar options, and seat mast options and rear wheel /drive train options.


If you have a passenger train does it have roll on roll off service? or must you fold the bike compactly to bring it with you?

[People tour in Bromptons too ]




.....

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Old 12-19-17, 06:17 PM
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Originally Posted by tomtomtom123 View Post
There are 2 knobs at the bottom of each end of the rear frame,... (Snip)

The seat tube is to the side of the main frame. Are the wheels in the same plane? (Or perhaps, the handlebar is to turn left slightly to go straight ...)
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Old 12-19-17, 06:23 PM
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It says Dahon Matrix. Perhaps with this kind of hinge config (similar to Visc), if there a slight deformation of the main hinge, the effect is amplified on the top connection.
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Old 12-19-17, 06:26 PM
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The SPIN seatstay arrangement is not exactly like you describe it.

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Old 12-19-17, 06:51 PM
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Originally Posted by dahoneezz View Post
The seat tube is to the side of the main frame. Are the wheels in the same plane? (Or perhaps, the handlebar is to turn left slightly to go straight ...)
From some of the other photos on their website, I think the rear frame is welded at a slight angle to face towards the handlebar. It means there's only one point of convergence, which is probably when fully extended. Probably when the rear frame gets closer to the front, the convergence becomes slightly off. Looking downwards while seated, there would be a beam going from one side of your seat towards the center ahead of you.

It also means that any rear rack has to slide under the beam. It cannot go over the beam because the beam would hit the left stays of the rack as you attempt to telescope.
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Old 12-19-17, 07:14 PM
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Another option might be S & S couplers. If you already have a standard bike you like;
just modify the frame. Or buy a new frame and use parts you already have.
Folding Travel Bikes using S and S Machine Bicycle Torque Couplings™
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Old 12-19-17, 07:38 PM
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Originally Posted by Abu Mahendra View Post
The SPIN seatstay arrangement is not exactly like you describe it.


What I meant was that the seatstay / chainstay on the Spin acts as a single member, compared to the "standard" triangle. It would have a lot of internal stress. You could say the same thing about all folding bikes with a single top tube that goes straight across from the seatpost to the handlebar, but to compensate, the beam either has thicker walls or is taller in height. Increasing the height increases the amount of bending it can take, which is what I thought was the reason for the design of the Visc hinge.

I think the main front frame of the Tyrell IVE is very stable because they were able to fit in a large triangle. This reduces bending from the top tube and downtube, so they only have to resist buckling. Both wheels also lock in place when folded, and can still be rolled. You're also not stuck with a proprietary rear rack that needs to fold down, and can still roll with your own rack. The problem is that the max load is 85kg, maybe because of the 120mm hub, or the the asymmetric 3 stays at the rear? I don't see why they didn't go for 130mm.
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Old 12-19-17, 08:08 PM
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Originally Posted by fietsbob View Post
Bike Friday is the Only one with several frame (Length) sizes , all the others just make one..

Brompton's just make one.. But they have bar mast.handle bar options, and seat mast options and rear wheel /drive train options.

If you have a passenger train does it have roll on roll off service? or must you fold the bike compactly to bring it with you?
The current bike I have is a Dahon with a T bar stem. I was able to adjust my reach by changing the length of the stem extender, but there aren't many lengths available (I could only find 2). It's off by about 1-2cm from what I would like but it's ok for the moment. Having a "standard" type stem like on the BF or IVE would give more options.

6 gears on the Brompton is not enough for me. I'm using a 3x9 dual drive and have 17-89 GI. If I can't transfer over the dual drive to a new bike, I would use a 1x10 11-36T cassette on the new bike for 25-80 GI.

Rolling a folded bike should be a given in the design. It's something that is very convenient in multiple scenarios. If all I had was the bike, carrying it a short distance while folded is not a problem, but if I've got 4 panniers, or a heavy backpack, or I'm transporting some heavy supplies across town, I wouldn't be able to carry them all for very long.

The trains are sometimes packed and I have to go from one end to the other to find an open seat. I'd prefer rolling the folded bike through the isle instead of carrying it.

In a one off scenario, I was traveling with my bike in another country, where folded bikes in a bag were allowed on the train, but I wasn't allowed to take the bike out of the bag until I was out of the station. I had to carry it folded, along with my panniers from the platform to the exit of the station which took me several minutes of stop and go while I rested my arms, and the platform conductor followed me all the way out to make sure I didn't take the bike out of the bag. If I had inserted the bike the other way around into the bag, I could have exposed the wheels and rolled it instead.

I've seen in some of the youtube videos of the BF bikes where when folded, the rear wheel is tied to the top tube with a velcro strap so that it doesn't drop when rolling on the front wheel. But it looks a bit cumbersome. The Birdy and IVE both use the seatpost to hold the rear wheel in place. But the BF seatpost tube ends on top of the BB so it can't pass through. The other odd thing is that when resting a folded BF bike without add on parts, it looks like the chainring / chainguard touches the ground. Also, the seatstay ends are exposed and touch the ground. The seatstay ends on the BF PC don't connect together, so they're floating freely when disconnected from the seatpost tube. I think there's a risk of them getting bent, for example when you place it in the cargo hold of the bus with other shifting baggage. In contrast, the stays on the Birdy and IVE are one "block". Their weak point when folded would be the pin behind the BB, although the IVE has some adjustment screws in the little pocket of the rear frame where the seat tube goes into when folded, to make it fit snugly.

The benefit of the telescoping design of the Giatex is that the structure isn't compromised when "folded", it's simply compressed.

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Old 12-20-17, 10:47 AM
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I have a bolt on bracket, to mount a front derailleur on a Brompton, to fit a double chainring and have the shifting done with a handle bar lever..

Will Sell..

I instead chose to use the Swiss made Schlumpf 2 speed planetary gear crank, it spreads out the AW3/ BSR 3 speeds to be used twice

Low on low range 17 " (15x'21.6') high range 15:54 a 50t acts like a 20t, more even numbers .
crank arms turn that much faster thru the gear box than the chain ring..

but a folded Brompton only rolls on its rear rack wheels ... would not drag it the full length of an 8 car train..Folded.
... there is a locking mech in the BF Tikit , to roll it on its front wheel .

the new PakIt has a different way to do similar, roll on the front wheel while folded..
you probably could order it with the latest 1 by 10.. drivetrain .

I have no dealers selling any on your list (other than a daHon, In my town, in Oregon, by the sea)
(I used to live in the town where the Bike Friday company is, and knew the founders)

IDK where you are, Good Luck, (you can write a lengthy(obviously) revue of what you finally choose)

[In the past there was a thread on a custom builder in China making a Titanium variation of the Swift, a 20" wheel bike
that uses it's seat post to join 2 sections of the seat tube , to fold there..] ..



....

Last edited by fietsbob; 12-20-17 at 11:02 AM.
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