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Bastille Folding Bike (France)

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Bastille Folding Bike (France)

Old 06-02-24, 11:00 PM
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There's a huge bifurcation between folders that are compact enough to be easily carried and checked on an airline with no oversize charges, and folders that can fit on the train luggage rack and in a car trunk.

Before I knew anything at all about folders, I didn't throw darts at a board, I chose my 20"/406 folder based on the smallest wheel I could have, while having sufficient high gear without an IGH for an overdrive, or a monster chainring. Everything else took me years to learn. There are definitely superior designs over mid-frame bi-fold, mine won't meet airline checked bag size, without diassembly, and I think packing in two parcels. For a tour capable, fast-and-easy-checked-bag-packed-size (not oversize) folder, my conclusions so far:
- A 20" brompnot (trifold) might make it in size, but still needs a hinge on the main tube, and if further forward than a bifold, does get less bending moment, but the same torsional loading when climbing as all other designs, and I always notice looseness there first. For a rear rack with full pannier loads, it might also require a firmly locked rear triangle (like a Bike Friday 20"), without the rear suspension movement, so all lateral rocking loads do not go through the hinge point, which may feel flexy. A 20" trifold should meet airline checked bag standard size limits, without disassembly.
- The Helix design (24") would not be any smaller with 20", as 24" fits within the frame envelope. The problem there is poor tire selection in 24". They might be able to shrink the frame to 20" proportions with a bit less wheelbase, and a handlepost canting more forward, instead of parallel with the seat post. Same notes as above regarding rear rack loads. No main frame hinge, that's good. The current Helix will meet airline checked bag standard size limits, so a frame proportioned for 20" wheels should be at least as good. So far, that would seem a leading candidate for me, but it's currently less-than-vaporware, it's merely mind-ware.
- A Bike Friday 20" swinging-rear-triangle fold, is a lot larger because the frame main tube does not fold. BFs are as big as a bifold, if not a touch bigger. BFs only get small by pulling off both wheels and the handlepost, a lot of time and effort.

So except for airline travel, or hand-carrying signficant distance, my 20" bifold is adequate. Air travel, TBD.

Last edited by Duragrouch; 06-02-24 at 11:05 PM.
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Old 06-03-24, 12:01 AM
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Originally Posted by Duragrouch
There's a huge bifurcation between folders that are compact enough to be easily carried and checked on an airline with no oversize charges, and folders that can fit on the train luggage rack and in a car trunk.

Before I knew anything at all about folders, I didn't throw darts at a board, I chose my 20"/406 folder based on the smallest wheel I could have, while having sufficient high gear without an IGH for an overdrive, or a monster chainring. Everything else took me years to learn. There are definitely superior designs over mid-frame bi-fold, mine won't meet airline checked bag size, without diassembly, and I think packing in two parcels. For a tour capable, fast-and-easy-checked-bag-packed-size (not oversize) folder, my conclusions so far:
- A 20" brompnot (trifold) might make it in size, but still needs a hinge on the main tube, and if further forward than a bifold, does get less bending moment, but the same torsional loading when climbing as all other designs, and I always notice looseness there first. For a rear rack with full pannier loads, it might also require a firmly locked rear triangle (like a Bike Friday 20"), without the rear suspension movement, so all lateral rocking loads do not go through the hinge point, which may feel flexy. A 20" trifold should meet airline checked bag standard size limits, without disassembly.
- The Helix design (24") would not be any smaller with 20", as 24" fits within the frame envelope. The problem there is poor tire selection in 24". They might be able to shrink the frame to 20" proportions with a bit less wheelbase, and a handlepost canting more forward, instead of parallel with the seat post. Same notes as above regarding rear rack loads. No main frame hinge, that's good. The current Helix will meet airline checked bag standard size limits, so a frame proportioned for 20" wheels should be at least as good. So far, that would seem a leading candidate for me, but it's currently less-than-vaporware, it's merely mind-ware.
- A Bike Friday 20" swinging-rear-triangle fold, is a lot larger because the frame main tube does not fold. BFs are as big as a bifold, if not a touch bigger. BFs only get small by pulling off both wheels and the handlepost, a lot of time and effort.

So except for airline travel, or hand-carrying signficant distance, my 20" bifold is adequate. Air travel, TBD.
In your list, you do forgot folding bikes with a one piece not folding main frames like the Birdy, the Tyrell Ive, the Vellobike, the Ori, the Iruka. Some have a rear rack compatible with full size rear pannier and/or front low riders.
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Old 06-03-24, 01:02 AM
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Originally Posted by Jipe
In your list, you do forgot folding bikes with a one piece not folding main frames like the Birdy, the Tyrell Ive, the Vellobike, the Ori, the Iruka. Some have a rear rack compatible with full size rear pannier and/or front low riders.
Well I had kinda thought the Bike Friday 20"ers were indicative of that, but if there are others with a lot shorter main tube, that may make a difference. I'm just not familiar with enough of them. I'll have to brush up on them. One I saw, I think did so at the expense of reduced wheelbase in front.

There isn't by chance in one of the folder stickies, a comprehensive list of folders, separated by type?
- bifold (main tube lateral hinge)
- trifold (underswinging rear + main tube lateral hinge)
- horizontal hinge (latched or gravity-locked)
- telescoping

... and most especially, which meet 62" max combined girth for aircraft checked bag.

I'll have to look around for a list. I'm the kind of person who will read aircraft encyclopedias like a Jane's from cover to cover.

EDIT: I looked at the models you mentioned, thanks for that.
- The Ori/Mezzo, I like the monobeam frame, by moving the front wheel aft then extending the steering way out for knee clearance; I'd like to ride one to evaluate if easier to tip forward under hard braking, and steering dynamics.
- Iruka seems to combine typical swinging rear triangle, with a different means than Helix of accomplishing a folding fork. Not as compact as a Brompton, but a package as low and a bit longer, might fit 62".
- Vello, also seems to have a folding fork.
- Tyrell Ive, ALSO a folding fork; I'd be curious if all these folding-fork designs were around before Helix, or all invented in response to it. In all cases, I think the folding fork is only of value with an underswinging rear triangle, it won't make a bifold shorter.
- Birdy I know of, looks like the best suspension for ride.

I'll have to investigate all. Tyrell Ive seems the most elegantly simple design to me; But just a couple inches above 62" combined girth, and 355 tires, I would prefer either 349 or 406 for supply here in the USA. Can't find gearing details in specs to see if gearing high enough for me.

Y'know... if someone makes an aftermarket folding fork... fit to a bike friday (either NWT or diamond frames), plus a typical folding handlepost, I'd basically have the Tyrell Ive design. I'll have to sketch that out, see how much it shrinks a BF with the wheels still on... Nope, not quite, because BF rear wheel does not overlap the frame tube when folded, that needs to happen to line up with a folded fork. And folding fork not needed, not for only air travel; Any fork with internal threads and center preload bolt like on Dahons, that's a quick fork on and off, just fold the handlepost, loosen the clamp bolt and remove the preload bolt, and the fork and handlepost separate. Gonna have to think on this.

Last edited by Duragrouch; 06-03-24 at 02:10 AM.
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Old 06-03-24, 06:24 AM
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Originally Posted by Duragrouch
- A 20" brompnot (trifold) might make it in size, but still needs a hinge on the main tube, and if further forward than a bifold, does get less bending moment, but the same torsional loading when climbing as all other designs, and I always notice looseness there first. For a rear rack with full pannier loads, it might also require a firmly locked rear triangle (like a Bike Friday 20"), without the rear suspension movement, so all lateral rocking loads do not go through the hinge point, which may feel flexy. A 20" trifold should meet airline checked bag standard size limits, without disassembly.
TBD.
Question, have you ever ridden a Brompton?. Having had a couple of Dahons in my past, probably fifteen years ago or so, I see how you can make assume the hinges would be fiddly in torsion and flexy. When I took my first ride on a Brompton I was surprised how stiff it felt. I don't do much hill riding here in Flatlandia. Occasionally, I have to ride over a levy, and they are steep but short, and you often don't get a running start, I would agree that it would be better to have no hinges in the main tube, but Brompton's hinges are strong and stout. I would not try to sell you on a Brompton. They should have compromised on the size a little and gone with 355 wheels and left room for 2-inch tires with fenders. Though if they did that, it might have made airline travel more problematic. The rear shock does compromise the ride to an extent but less so than a front shock. I would not assume that since the bike works as a 16 inch, it will as a 20 inch. Maybe but no certainty on that. Time will perhaps tell. Inside sources tell me that a 20 inch Brompton is undergoing testing right now.
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Old 06-03-24, 06:41 AM
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Originally Posted by Duragrouch
I'd be curious if all these folding-fork designs were around before Helix, or all invented in response to it.
Long before.

Not as compact as a Brompton, but a package as low and a bit longer, might fit 62".
In addition to expected folding bike design goals, the Iruka had an additional design goal: fit between the seats of a Shinkansen bullet train. That's why the fold is low and subsequently wide.
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Old 06-03-24, 11:46 PM
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From my knowledge, its Tyrell who released the first reliable folding fork on its race folding bikes?

Vello more or less copied the Tyrell solution in a less clean design and manufacturing (Tyrell manufacturing is gorgeous, not only the XF with titanium frame but also the FSX and FX with aluminum frame, its a pity they don't fit for most European riders).

Indeed, Iruka wasn't designed to fit for air travel but well for train travel in Japan.
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Old 06-04-24, 04:41 AM
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Originally Posted by Schwinnsta
Question, have you ever ridden a Brompton?. Having had a couple of Dahons in my past, probably fifteen years ago or so, I see how you can make assume the hinges would be fiddly in torsion and flexy. When I took my first ride on a Brompton I was surprised how stiff it felt. I don't do much hill riding here in Flatlandia. Occasionally, I have to ride over a levy, and they are steep but short, and you often don't get a running start, I would agree that it would be better to have no hinges in the main tube, but Brompton's hinges are strong and stout. I would not try to sell you on a Brompton. They should have compromised on the size a little and gone with 355 wheels and left room for 2-inch tires with fenders. Though if they did that, it might have made airline travel more problematic. The rear shock does compromise the ride to an extent but less so than a front shock. I would not assume that since the bike works as a 16 inch, it will as a 20 inch. Maybe but no certainty on that. Time will perhaps tell. Inside sources tell me that a 20 inch Brompton is undergoing testing right now.
I have not yet ridden a Brompton. I think their forward frame hinge may clamp like the later Dahon (I think Mu) hinge, which stays tight. My bigger concern is on any model with an underswinging rear triangle that "floats" when unfolded to provide suspension (a plus), I wonder if, loaded with panniers, if that rear triangle would feel noodly, when climbing and rocking the bike. Not due to bobbing, but if any twist. Helix has a touring rack and runs that setup (can't recall if the rear is fixed at top, or moves as suspension). Bike Friday fixes the seatstays when unfolded, so probably good in torsion there. I don't think this would be an issue unless heavily loaded rear panniers, mounted well above the rear triangle pivot, so the chainstays are taking all the torque, and those are essentially a "ladder frame", which typically are not great in torsion, not a big enough torque box. Anyway, this is all brain wondering, it may not be true at all in actuality.

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Old 06-04-24, 11:59 AM
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Your views would hold more weight if they were based on experience rather than analysis. Plenty of dealers around to take a test ride.

The rear triangle is pinned at the bottom and at the top (even when unlatched if under gravity load of the rider), Panniers would be too small to be of much use on the rear rack. I don't get a noodley feeling, but I seldom pedal out the seat.
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Old 06-04-24, 04:14 PM
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Originally Posted by Schwinnsta
... I seldom pedal out the seat.
Good. Because that's now obsolete. 😉
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Old 06-04-24, 06:33 PM
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Originally Posted by Schwinnsta
Your views would hold more weight if they were based on experience rather than analysis. Plenty of dealers around to take a test ride.

The rear triangle is pinned at the bottom and at the top (even when unlatched if under gravity load of the rider), Panniers would be too small to be of much use on the rear rack. I don't get a noodley feeling, but I seldom pedal out the seat.
Yeah, a low rear rack close over the rear wheel (like what came with my bike) is most efficient in terms of cargo space, but I had to install a "high" (large wheel bike) rear rack, both to hold full-size panniers high enough to not scrape curbs, and to hold them behind the axle for heel clearance. But that means a 6" gap between the rack and the tire, wasted space. On a loaded tour, I might try to figure out how to strap something there.

Like I clearly said, I'm just speculating about some of the above based on structural knowledge. I was not making a statement, but asking a question. I would LOVE that I would be wrong. I should test ride a Brompton, I just typically don't feel right about test riding something that I am not currently in the market for. However, the bikes in the store are not equipped to hold loaded panniers, so that test ride won't answer my question. Most folks loaded-touring on a Brompton use a medium backpack sitting upright on the rack and strapped to the seatpost (thus the seatpost is taking any lateral loads), plus the giant handlebar bag. There's gotta be someone here on the forums who as (any) swinging-triangle bike who has ridden it with loaded panniers and climbed with it, who could answer my question. Related question: I had also wondered in the past if on such bikes, if the pivot has a bushing that is replaceable, not just a bolt through plate hole on each side. With pannier loads, that might add wear there.
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Old 06-04-24, 07:46 PM
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Originally Posted by Duragrouch
There isn't by chance in one of the folder stickies, a comprehensive list of folders, separated by type?
- bifold (main tube lateral hinge)
- trifold (underswinging rear + main tube lateral hinge)
- horizontal hinge (latched or gravity-locked)
- telescoping
With your four types, how would you categorize:
- Birdy
- Strida
- Big Fish
- DiBlasi
- CarryMe
- FiveLinks & Ossby
- Hummingbird & BikeFriday pakit
- Mobiky & Jango Flik
- Scooma & Picnica
- Jifo & EEZZ
- Whippet
- Xootr
- Ori & Anemos
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Old 06-04-24, 07:55 PM
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Originally Posted by tcs
With your four types, how would you categorize:
- Birdy
- Strida
- Big Fish
- DiBlasi
- CarryMe
- FiveLinks & Ossby
- Hummingbird & BikeFriday pakit
- Mobiky & Jango Flik
- Scooma & Picnica
- Jifo & EEZZ
- Whippet
- Xootr
- Ori & Anemos
Oh I knew when I listed those four types, there were a lot more. I just couldn't think of them all. So that was not an inclusive list, I know. I'd just like to find a complete list online, with easy links, and sorted by wheel size and type. There used to be in paper copy, annual buyer's guides for many product categories that had nearly everything, I wondered if there was the same for folders. It's been many years, but back in the early days, I think there may have been such associated with Recumbent Cycling News, perhaps one issue annually, not sure.
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Old 06-04-24, 08:04 PM
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Originally Posted by Duragrouch
Yeah, a low rear rack close over the rear wheel (like what came with my bike) is most efficient in terms of cargo space, but I had to install a "high" (large wheel bike) rear rack, both to hold full-size panniers high enough to not scrape curbs, and to hold them behind the axle for heel clearance. But that means a 6" gap between the rack and the tire, wasted space. On a loaded tour, I might try to figure out how to strap something there.

Like I clearly said, I'm just speculating about some of the above based on structural knowledge. I was not making a statement, but asking a question. I would LOVE that I would be wrong. I should test ride a Brompton, I just typically don't feel right about test riding something that I am not currently in the market for. However, the bikes in the store are not equipped to hold loaded panniers, so that test ride won't answer my question. Most folks loaded-touring on a Brompton use a medium backpack sitting upright on the rack and strapped to the seatpost (thus the seatpost is taking any lateral loads), plus the giant handlebar bag. There's gotta be someone here on the forums who as (any) swinging-triangle bike who has ridden it with loaded panniers and climbed with it, who could answer my question. Related question: I had also wondered in the past if on such bikes, if the pivot has a bushing that is replaceable, not just a bolt through plate hole on each side. With pannier loads, that might add wear there.
There are many, I think, on the forum or who were who ride with a backpack on the rack. 2 I comes to mind for one. I keep my rack free to use it to roll the bike inside places on the easy wheels. I do use a beam rack of sorts on the seat post. Since you are into Structural let me ask you if the effect at the locking point at the top of the rear triangle do to side thrusts is similar, more, less than if the load was on rack?

To my knowledge, any part on a Brompton can be had through their dealers, even for old Bromptons.

But again I would advise you to test a Brompton even if you are not ready to buy one. I see nothing wrong with that. Just explain to the dealer you would like to test drive but you are not ready to purchase. Some might let you rent. My dealer does both.
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Old 06-04-24, 08:30 PM
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Originally Posted by Schwinnsta
Since you are into Structural let me ask you if the effect at the locking point at the top of the rear triangle do to side thrusts is similar, more, less than if the load was on rack?
That's an excellent question, one I wonder about. Again, I do not know if that is necessary, but for it to benefit, the top point on the triangle (seatstay/seatpost) must be fixed both laterally for movement (easy if a tight latch), but also be fixed in lateral rotation, so moment can be transmitted through the joint. The seatstays are loaded in both compression and lateral bending. The above "end condition" is critical in analysis of structures (in particular, buckling columns, for example), as to whether "fixed" (like welded or somehow joined fully), or "pinned" or "ball" joint where the end is not fixed in rotation. Makes a big difference. I've noted with Bike Friday 20" frames with a swinging rear triangle and no suspension, the seatstays are rigidly attached at the top of the seat tube with a quick-release spindle (just like QR wheels), and that fixes things in both lateral position and lateral moment (though could overpower friction and rotate in vertical bending moment). BFs were originally designed to haul gear in the carry suitcase converted into a trailer, no big cargo loads into the frame, but either from the start or later on, people wanted to be able to pannier loads with no trailer, and I think that rigid seatstay attachment may be critical for that, I don't know for certain. They have a good reputation for touring durability. Now, their folding rear rack, I could see a mile away, has some structural weakness by my perception, and a fellow who toured *hugely* on a BF (big and superb blog), said that it broke pretty quick and he needed to replace with a proper rack. Some structural things just jump out at me.
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Old 06-04-24, 11:53 PM
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Originally Posted by Duragrouch
Yeah, a low rear rack close over the rear wheel (like what came with my bike) is most efficient in terms of cargo space, but I had to install a "high" (large wheel bike) rear rack, both to hold full-size panniers high enough to not scrape curbs, and to hold them behind the axle for heel clearance. But that means a 6" gap between the rack and the tire, wasted space. On a loaded tour, I might try to figure out how to strap something there.
For me the best solution is the folding rear rack of the Birdy that automatically folds when the rear swing arm is folded and accepts full size rear pannier with enough heel clearance.









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Old 06-05-24, 01:46 AM
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(above) You've mentioned that before (and I definitely don't mind you mentioning it again), it's cool, it rocks, definitely good for a frequent folder. That's a lot of cantilever length, but it looks well made, increased beam depth of section where it would need it. Is it aluminum or chrome-moly steel? Do you know the weight limit rating? That'll tell me a lot. Thanks. It might need something to keep the panniers from laterally banging on the fenders. The experienced bike friday tourer, got rid of the normal spring hook or other on the inboard of the pannier, would break, he would strap both panniers to each other, a big strap all the way around the panniers horizontally, that worked good. He also rigged straps under each lower pannier corner up to the rack, this greatly prolonged life of the upper rack clips. Tons of useful wisdom on that guy's blog.

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Old 06-05-24, 02:48 AM
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I added the pictures to show how it works.

Its made of aluminum and rated for 15kg max.

The system includes a tube to attach the low hook of pannier like those of Vaude and Ortlieb and prevent lateral banging: its the black thick, strong, vertical aluminum tube that also holds the rear mudguard. The hook of the pannier must be placed horizontally so that it slides on the vertical tube when the rear suspension is compressed.

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Old 06-05-24, 03:59 AM
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(above) Pannier hook: Oh, very slick. Yeah, somebody was thinking. 15kg is plenty for town errands. Not enough for touring, but that's not what it was designed for. But very good as a townie. Mine's the opposite, I think 25kg IIRC, but I'll need to take the rack off for flight packing the bike.
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Old 06-05-24, 04:49 AM
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There are also a front rack for two low riders (10kg max) and a Brompton front block adapter for a Brompton front bag (10kg).

In total 35kg, that enough for touring and easy to use, all 5 bags can be installed/removed quickly, much easier to use that the multitude of small bike packing bags attached on the bike with velcro and straps .



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Old 06-05-24, 06:35 AM
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Originally Posted by Duragrouch
That's an excellent question, one I wonder about. Again, I do not know if that is necessary, but for it to benefit, the top point on the triangle (seatstay/seatpost) must be fixed both laterally for movement (easy if a tight latch), but also be fixed in lateral rotation, so moment can be transmitted through the joint. The seatstays are loaded in both compression and lateral bending. The above "end condition" is critical in analysis of structures (in particular, buckling columns, for example), as to whether "fixed" (like welded or somehow joined fully), or "pinned" or "ball" joint where the end is not fixed in rotation. Makes a big difference.
I would say that for the Brompton the rear triangle is pinned where it is connected to the main frame, both at the seat stays and at the chain stays. Those joints can carry no moment. I take fixed joints to be welded ones, mostly for modeling bicycles.

Here is an interesting read for getting a flavor of touring on a Brompton.
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Old 06-06-24, 12:29 AM
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Originally Posted by Schwinnsta
I would say that for the Brompton the rear triangle is pinned where it is connected to the main frame, both at the seat stays and at the chain stays. Those joints can carry no moment. I take fixed joints to be welded ones, mostly for modeling bicycles.

Here is an interesting read for getting a flavor of touring on a Brompton.
Yeah, swinging triangles that "latch" up top, I think would be fixed lateral, but perhaps not in moment, but that only would matter if analyzing the seatstays; For purposes of the triangle lateral rigidy there with respect to frame, it would be rigid. But I thought Bromptons don't latch there, just push on a rubber bumper? I'll have to look at one close.

The link about the pac coast trip on a Brompton, is excellent, and confirmed a number of things.
- Rims heat up too much on long descents, especially small wheels, like his 349s and my 406s. People here have said rim brakes have been used forever, blah blah, but I live in hills and I've popped drive-side spokes from overheating the rear rim (aluminum, large coefficient of thermal expansion) on long descents, so I want DISCS.
- Big heavy bag supported at front block, non-steered: An excellent university study determined non-steered weight there, improves stability (tiny wheel bike was still stable with zero trail/caster and wheel inertia canceled). My bike weight there is steered but low and close to steering center, and helps calm steering. Higher and forward cargo on platform, I can feel it if heavy, but low density loads there are fine.
- Monster seat bag does keep all lateral loads off of rear triangle. Might feel a bit sluggish if rocking the bike when climbing. My rear pannier load is way lower, so my handlebar forces have plenty of leverage against that.
- So both of his choices above may be a perfect setup on a Brompton. If there was a way to hold that rear bag lower on the seatpost but clear of rear triangle, legs, and heels, might be a bit better in stability and stress on the seat tube.
- I'd be carrying a bit more cargo. I'm a cold sleeper, so like he said, warmer bag. Tent and insulation-filled air-pad. Liquid or canister fuel stove, alcohol and solid fuel stoves I've tried, nearly useless, lose heat at pot almost as fast as inputting it.
- His gearing setup, BWR 6-speed, should be 300%, not quite enough for me, I need 400%, don't need more, can't do with less in hills. I ran into a guy here touring on a Brompton, he installed a Schlumpf drive at the crank, to get that extra range. My guess is future Bromptons will have wider gear range as option.
- You just can't carry enough water on long stretches. I also have a water filter, have yet to use it in 30 years now, but always have it along if traversing remote areas with wild water.

I'd also like to do a pac coast trip, but would like to stay on the ocean if possible. But my one short stint there on a trip, man does bike and sunglasses get full of salt dust quick, and this was a blue-sky sunny day. Waxing drivetrain in place of oil might help there.
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Old 06-06-24, 04:14 AM
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Yes, rim heat up is a known problem with small diameter wheels. In case of downhill but also for fast small wheels bike like recumbent. And the rim wear faster if it has a small diameter. So disc brakes at least for the front wheel is useful in case of small wheels.

Brompton has now a 12s 3x4 transmission made of a variant of the BWR hub and the 4s derailleur of the P-line and T-line with a wide range, its not ideal but it at least exists. For the T-line its for me nonsense because you will pay a lot of money to save weight on the frame to loose this weight gain with a poor 3s IGH but for the T-line its an improvement of the 6s.

For traveling, a 12s Brompton can do the job but a Birdy is much better (possibility to use front and rear pannier, more efficient, better transmission with a real derailleur pr a Rohloff, wide tires, full suspension...).
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Old 06-06-24, 06:14 AM
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Originally Posted by Duragrouch
Yeah, swinging triangles that "latch" up top, I think would be fixed lateral, but perhaps not in moment, but that only would matter if analyzing the seatstays; For purposes of the triangle lateral rigidy there with respect to frame, it would be rigid. But I thought Bromptons don't latch there, just push on a rubber bumper? I'll have to look at one close.

The link about the pac coast trip on a Brompton, is excellent, and confirmed a number of things.
- Rims heat up too much on long descents, especially small wheels, like his 349s and my 406s. People here have said rim brakes have been used forever, blah blah, but I live in hills and I've popped drive-side spokes from overheating the rear rim (aluminum, large coefficient of thermal expansion) on long descents, so I want DISCS.
- Big heavy bag supported at front block, non-steered: An excellent university study determined non-steered weight there, improves stability (tiny wheel bike was still stable with zero trail/caster and wheel inertia canceled). My bike weight there is steered but low and close to steering center, and helps calm steering. Higher and forward cargo on platform, I can feel it if heavy, but low density loads there are fine.
- Monster seat bag does keep all lateral loads off of rear triangle. Might feel a bit sluggish if rocking the bike when climbing. My rear pannier load is way lower, so my handlebar forces have plenty of leverage against that.
- So both of his choices above may be a perfect setup on a Brompton. If there was a way to hold that rear bag lower on the seatpost but clear of rear triangle, legs, and heels, might be a bit better in stability and stress on the seat tube.
- I'd be carrying a bit more cargo. I'm a cold sleeper, so like he said, warmer bag. Tent and insulation-filled air-pad. Liquid or canister fuel stove, alcohol and solid fuel stoves I've tried, nearly useless, lose heat at pot almost as fast as inputting it.
- His gearing setup, BWR 6-speed, should be 300%, not quite enough for me, I need 400%, don't need more, can't do with less in hills. I ran into a guy here touring on a Brompton, he installed a Schlumpf drive at the crank, to get that extra range. My guess is future Bromptons will have wider gear range as option.
- You just can't carry enough water on long stretches. I also have a water filter, have yet to use it in 30 years now, but always have it along if traversing remote areas with wild water.

I'd also like to do a pac coast trip, but would like to stay on the ocean if possible. But my one short stint there on a trip, man does bike and sunglasses get full of salt dust quick, and this was a blue-sky sunny day. Waxing drivetrain in place of oil might help there.
You might have missed the part at the beginning where he added a chainring.at the front so he had a 12-speed. I think he may have been switching chain rings manually.
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Old 06-06-24, 08:13 AM
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Originally Posted by Schwinnsta
Here is an interesting read for getting a flavor of touring on a Brompton.
Cool story - that part of California is beautiful and wild! But it must be noted that the story is published on a website that sells Bromptons, so there may be some bias involved.
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Old 06-06-24, 08:15 AM
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Originally Posted by Jipe
For traveling, a 12s Brompton can do the job but a Birdy is much better (possibility to use front and rear pannier, more efficient, better transmission with a real derailleur pr a Rohloff, wide tires, full suspension...).
Do you tour with a Birdy? I'd love to see photos of the bike set up for it. They're such cool bikes.
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