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Contemplating a Birch Folding Bike Purchase: Wise Investment or Regrettable Decision?

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Contemplating a Birch Folding Bike Purchase: Wise Investment or Regrettable Decision?

Old 02-13-24, 01:53 AM
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Originally Posted by tcs
By what mechanism do they 'own' a design patented over 30 years ago?
Riese & Müller and Pacific Cycles aren't competing against each other, they are partners.

There are commercial agreements between Riese & Müller and Pacific Cycles, the several Birdy frames were designed by Riese & Müller and manufacturing subcontracted to Pacific Cycles who also received the right to sell the Birdy in several countries (mainly Asia, while Riese & Müller reserved for themselves the European market and I think also US, I do not know for other parts of the world like South America).

Its a kind of win-win agreement between Riese & Müller and Pacific Cycles because Pacific Cycles is a relatively small company without resellers outside Asia and Riese & Müller benefit from the resellers network of Pacific Cycles in Asia.
For the manufacturing of the frame, I think that Riese & Müller doesn't need Pacific Cycles anymore, they now have own manufacturing capabilities in Portugal were the frames of their ebikes are made.

Pacific Cycles has also commercial agreements with Hase to sell one of the Hase trikes in Asia.

Like for the Brompton clones, there are also some Birdy clones in Asia.
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Old 02-13-24, 05:55 AM
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Originally Posted by splithub
What about support materials, workmanship hours, taxes? Never heard of? I see. Since a certified dealership has to do that, embedded in a D-Check inspection.
The stem price is VAT included (for EU Birdy Owners).

For the support material, workmanship hours that you think will be very expensive, you obviously don't know how the Birdy stem is mounted !
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Old 02-13-24, 06:25 AM
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Originally Posted by Ron Damon
The new Sw!ft could have, should have moved to these standard, modern, flexless handleposts. But alas that was not the path taken. An opportunity lost.
I came across this topic when i wanted to convert my Mini Velo to a leftover Dahon Jetstream handlepost. As per the pictures, there are external bearing cups and therefore standard bicycle headset bearings in the steerer tube of the Swift frame. Folding bike headsets are different, carrying a greater axial preload. When you tighten the headset on a standard bike, you tighten it lukewarm. If you do it the way you do when installing the folding stem on a folder, it's locked or even ruined already, 11Nm? To fit a folders headset on the swift, it would need a more modern steerer tube, like MTB's have nowadays. That one on the swift is inherited from the first Swift made of steel, the most simple solution, and still good for standard applications.
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Old 02-13-24, 06:31 AM
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Originally Posted by Jipe
The stem price is VAT included (for EU Birdy Owners).

For the support material, workmanship hours that you think will be very expensive, you obviously don't know how the Birdy stem is mounted !
The manufacturer calls another price than your blowout sale discount online shop. Don't worry, i take care of that, it's rolling. My local Birdy dealer is on it, and btw. takes 85€ per hour before tax. Inspection costs are fix, material goes extra. You seem not to understand what's going on, i pick you apart for lying, and i will not stop, whatever you do :-)
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Old 02-13-24, 01:31 PM
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Originally Posted by Jipe
The stem price is VAT included (for EU Birdy Owners).

For the support material, workmanship hours that you think will be very expensive, you obviously don't know how the Birdy stem is mounted !
Jipe I asked you a couple of times does Birdy adjustable handlebar flex? You have yet to answer. It has been my experience that adjustable handlebars do flex.
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Old 02-14-24, 03:26 AM
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Sorry, I thought I answered your question.

By adjustable, I guess you mean adjustable in height?

I haven't tested the higher positions, but on the lowest and one step higher, there is no flex.

Originally Posted by splithub
The manufacturer calls another price than your blowout sale discount online shop.
Kemper Fietsen in Den Haag The Netherlands is an official Riese & Müller reseller that sells the Birdy. The prices of its online shop are official Riese & Müller prices.
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Old 02-15-24, 07:37 AM
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Hello Mr ...,

Thank you very much for your e-mail and your enquiry.


As you have already found out, the Birdy is subject to mandatory replacement of the stem tube, steerer tube and handlebars. These components must be replaced after an accident or 10000 km or 3 years (whichever comes first). This is a fixed obligation.
Failure to comply with this replacement obligation will have a negative effect on your warranty.

We hope we have been able to help you and will be happy to answer any questions you may have.

Best regards
Ihr Riese & Müller Customer Care-Team
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Old 02-15-24, 07:53 AM
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Originally Posted by Jipe
...For the 3 years stem replacement, its a recommendation as part of the maintenance plan in the Birdy user manual, its not mandatory...

...And it is a recommendation...

...There is no mandatory stem exchange...
...

Last edited by splithub; 02-15-24 at 07:58 AM. Reason: typo
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Old 02-15-24, 09:35 AM
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Originally Posted by splithub
Hello Mr ...,

Thank you very much for your e-mail and your enquiry.


As you have already found out, the Birdy is subject to mandatory replacement of the stem tube, steerer tube and handlebars. These components must be replaced after an accident or 10000 km or 3 years (whichever comes first). This is a fixed obligation.
Failure to comply with this replacement obligation will have a negative effect on your warranty.

We hope we have been able to help you and will be happy to answer any questions you may have.

Best regards
Ihr Riese & Müller Customer Care-Team
As I wrote, the only consequence of not replacing the stem is a negative effect on your warranty (i.e., the optional extra legal 10 years frame warranty because after 3 years the legal 2 years warranty is over).

They do not say that its a safety requirement, if it was, you can be sure that they would have warned!

Didn't you asked the price of the stem? If you had, you would know that the price of 190€ of Kemper Fietsen is the official price. And you should Google a little to find out how quick and easy it is to replace it!
Originally Posted by splithub
If you allow it, i would like to express that a flexy stem is the smallest stem problem a birdy owner can have, since he is obligated to replace the stem latest after three years for the price of a mid range folding bike, otherwise R&M refuses any responsibility, no matter what happens, agreed upon purchase. The fork has a similar exchange policy.
If you are not the first owner, R&M even reserves not to supply spares for you.
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Old 02-15-24, 09:54 AM
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Originally Posted by Jipe
Sorry, I thought I answered your question.

By adjustable, I guess you mean adjustable in height?

I haven't tested the higher positions, but on the lowest and one step higher, there is no flex
​​​​​​
Try it at half the max. At the lowest settings it acts as non adjustable.
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Old 02-15-24, 10:34 AM
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Originally Posted by Jipe
As I wrote, the only consequence of not replacing the stem is a negative effect on your warranty (i.e., the optional extra legal 10 years frame warranty because after 3 years the legal 2 years warranty is over).
No, after two years, the two year warranty is over. And if you reach 10000km before two years are over, for example if you ride 20km per day, the warranty is gone also if you don't get the stem replaced. And i have to add that i don't discuss topics i'm not interested in. I really just gave a small example for the reliability of your statements, i made the facts visible, contradicting your claims. Thank you
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Old 02-15-24, 03:06 PM
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Originally Posted by Ron Damon
The issue of sizing and reach is overstated. One reason is that unlike, say, a Birdy, Brompton and the Frankenstein Swift, the FSIR takes standard, non proprietary handleposts which come in a range of lengths and angles, including banana shape handleposts. These inexpensive, ubiquitous handleposts further allow the installation of extending stems, if needed. Beware the outdated notion of the channel gurus that there is flex in these handleposts or its mechanism. That's no longer the case in 2024 and for several years now. It's a concocted non-issue today, and a reflection of their bikes and their knowledge.
Most adjustable I have come across do flex. It becomes an issue for some folders like my Zizzo because the handlebar integrates into the fold, making the fold thinner. One has to rotate the grips then fully extend the bar such that it is below the wheel dropout. and magnets lock the halves. I would think, but I do not know, that the stem fitting to the bike is non-proprietary. Even if I bought a banana folding bar or single post, it would not fold well between the halves like the bar that is designed for the bike. I have had other folding bikes that used this same arrangement and think it to be somewhat common By the way, even though the Zizzo does flex a bit, that bike owes me nothing. I had at least one Dahon that use this folding method was way more flexy. In addition, the Zizzo was incredibly low-priced, $320 shipped, and is still a fine bike.

It appears to me that both the Swift and the FSIR trade some folding length for stiffness.
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Old 02-15-24, 04:33 PM
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Originally Posted by Jipe
As I wrote, the only consequence of not replacing the stem is a negative effect on your warranty (i.e., the optional extra legal 10 years frame warranty because after 3 years the legal 2 years warranty is over).

They do not say that its a safety requirement, if it was, you can be sure that they would have warned!

Didn't you asked the price of the stem? If you had, you would know that the price of 190€ of Kemper Fietsen is the official price. And you should Google a little to find out how quick and easy it is to replace it!
I see what you are saying, but any stem deterioration does not have an effect on other parts, like causing the frame to deteriorate. So them even suggesting replacement after 3 years, is a bad sign; They must have reason to believe the stem will fail in more prolonged use, and they want to avoid the liability of such. They would not recommend this if it was not a problem. Think about it, and the negative perception this presents to consumers. Not a safety problem? Why else would they give this warning? Because the finish is fading? Not likely. A handlebar stem is normally not considered a "wear and tear" item like tires, brake pads, chain, cogs, etc. If not a safety problem, if they are doing only to make money on the parts replacement (which does happen with other things, like Inkjet cartridges, a big source of income for HP), that also does not speak well of the company. I welcome your thoughts.
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Old 02-16-24, 02:38 AM
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Look at the user manual: safety issues are explicitly pointed out with "Danger" and "Attention" warnings (and there are a lot, 36 "Danger" and 26 'Attention").

The stem replacement is not a safety issue, its just a warranty limitation.

Warranty expiration of a product is not product end of life.

When the warranty of your car expires, you do not need to replace it.

Its the same for the stem.
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Old 02-16-24, 05:00 AM
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Originally Posted by Jipe
Look at the user manual: safety issues are explicitly pointed out with "Danger" and "Attention" warnings (and there are a lot, 36 "Danger" and 26 'Attention").

The stem replacement is not a safety issue, its just a warranty limitation.

Warranty expiration of a product is not product end of life.

When the warranty of your car expires, you do not need to replace it.

Its the same for the stem.
A number of car makers required periodic inspections, for the warranty to be valid, and replacement of worn parts, in addition to documented regular maintenance like oil changes and other lube. Regarding replacement of worn parts, after bad feelings from customers when the dealer says, "Your brake pads need replacing" and then being *required* to spend $1000 for that at the dealer, INSTEAD of being able to just have the local mechanic replace them for $500, or dealer oil changes at $250 versus $50 at Jiffy Lube, the auto companies, for goodwill, instead implemented "bumper-to-bumper" coverage; During the warranty, ALL maintenance is included for free, and ANYTHING that goes bad is replaced at zero cost to the customer. This results in a) proper maintenance and thus less warranty claims, and b) happier customers.

The problem with Birdy, it sounds, is they are not requiring periodic free inspections of the handelbar stem at a Birdy dealer, but rather are requiring replacement of the stem on a fixed schedule, regardless of use, or the *warranty is voided*, and that is a big penalty. That's like HP saying, if you don't use genuine HP inkjet cartridges, and buy them new and not refill them with a syringe, your entire printer warranty is void. I don't know exactly the terms of HP's warranties, but I do know customers were p!ssed about HP cartridge costs and found alternatives.

So, maybe the Birdy stem is not a safety issue. But they are requiring customers to spend big money for a genuine Birdy replacement stem, at genuine Birdy part costs, or else the customer *loses 80% of the warranty term*. That's a BIG penalty, borderline extortion, and even if legal, not conducive to customer goodwill.

There's an overlapping debate going on right now about "Right to Repair", laws being passed that allow consumers to have repairs done by folks other than the manufacturer, and the manufacturers are of course balking, because that is a big source of income for them, on such things as large farm equipment, necessitating a tech from John Deere to drive hours each way to hook up electronics to diagnose, and similar billed hours to lawyers, including travel time. This was on the news.

Do you want to be required to take your car to the manufacturer or dealer for every maintenance or repair? Do you want to be required to use only new dealer parts, at $500 for an alternator, instead of $125 for a rebuilt one at the local auto parts store?

Do you want to be able to fit a different aftermarket stem to a Dahon, without it completely voiding the warranty on the rest of the bike?

Now, understand, I do think some things should void a warranty. A pickup truck "lifted" a foot (or more) and much larger tires fitted, which overstress the brake and suspension components, yes, warranty voided, and I would go further in setting consumer liability for longer stopping distance and running over a car in front because the truck bumper is now too high. Cars having wheels spaced way out from stock ("stanced") and riding low on the bump stops ("slammed"), put tremendous excess moments and peak loads into the suspension, instant voided warranty. That is unreasonable stuff, in my opinion.

But having to replace the entire steering wheel and column assembly every couple of years, with only new OEM parts, at consumer expense, or your entire warranty is voided, no.

Discuss.

Last edited by Duragrouch; 02-16-24 at 05:17 AM.
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Old 02-16-24, 05:14 AM
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Originally Posted by Schwinnsta
Most adjustable I have come across do flex. It becomes an issue for some folders like my Zizzo because the handlebar integrates into the fold, making the fold thinner. One has to rotate the grips then fully extend the bar such that it is below the wheel dropout. and magnets lock the halves. I would think, but I do not know, that the stem fitting to the bike is non-proprietary. Even if I bought a banana folding bar or single post, it would not fold well between the halves like the bar that is designed for the bike. I have had other folding bikes that used this same arrangement and think it to be somewhat common By the way, even though the Zizzo does flex a bit, that bike owes me nothing. I had at least one Dahon that use this folding method was way more flexy. In addition, the Zizzo was incredibly low-priced, $320 shipped, and is still a fine bike.

It appears to me that both the Swift and the FSIR trade some folding length for stiffness.
As one who cut his teeth in cycling riding oversized Cannondale Al-alloy tube, rigid, suspension-less, diamond-frame MTB in the 1990s and is quite fastidious about and builds his bikes, I'd like to think that I know what rigid, flex-less means. And I think this flex thing on contemporary folders is overblown, and that manufacturers exploit it. It's up to you to take or reject their the bait.
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Old 02-16-24, 05:31 AM
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Originally Posted by Ron Damon
As one who cut his teeth in cycling riding oversized Cannondale Al-alloy tube, rigid, suspension-less, diamond-frame MTB in the 1990s and is quite fastidious about and builds his bikes, I'd like to think that I know what rigid, flex-less means. And I think this flex thing on contemporary folders is overblown, and that manufacturers exploit it. It's up to you to take or reject their the bait.
I agree. I'm very impressed with the rigidity of my (2004?) Dahon tapered steel one-piece stem. My other Dahon has a telescoping aluminum stem, and the upper has a bit more flex when climbing, but you really need to compare them side-by-side to detect the difference, so in other words, not a problem.

An old cheapie folder that I fixed up for a friend (he didn't want to worry if it got stolen), the long stem is skinny steel tubing, like handlebar tube diameter, and it flexes more, not enough to be problematic in safety and for the average consumer, it just might bug me when climbing, but again, not an issue for its target market.

A Cannondale road bike was my first good bike, I fell in love at first picture with that massive 2" down tube and Bicycling magazine's raving about the frame torsional rigidity for sprinting and the excellent value in terms of price. I loved the bike, but over time, grew less tolerant of the terrible ride quality, and fitting 28mm tires (just barely cleared the front derailleur) helped a lot.
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Old 02-16-24, 07:43 AM
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Originally Posted by Ron Damon
As one who cut his teeth in cycling riding oversized Cannondale Al-alloy tube, rigid, suspension-less, diamond-frame MTB in the 1990s and is quite fastidious about and builds his bikes, I'd like to think that I know what rigid, flex-less means. And I think this flex thing on contemporary folders is overblown, and that manufacturers exploit it. It's up to you to take or reject their the bait.
The point is not so much about stiffness / flex per se, but that it is not so easy as to change the stem on the bike and be done with it as you seem to suggest. In this case, Zizzo, but many others the design fold and the stem design are integral. Yes there is some flex of the stem, but the stem is designed to fit between the halves, resulting in a better fold.
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Old 02-16-24, 10:44 AM
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Originally Posted by univega.duder
Well, I'm glad I decided to pass on purchasing the Birch bike and grateful for those who advised against it; the latest Amazon review highlights alarming issues with frame welds coming apart Yikes!

I'm keeping my eyes peeled for a Swift or perhaps a used Bike Friday.



Big oof.
Dodged a bullet, Neo.
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Old 02-16-24, 12:17 PM
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Originally Posted by Duragrouch
So, maybe the Birdy stem is not a safety issue. But they are requiring customers to spend big money for a genuine Birdy replacement stem, at genuine Birdy part costs, or else the customer *loses 80% of the warranty term*. That's a BIG penalty, borderline extortion, and even if legal, not conducive to customer goodwill.

Do you want to be able to fit a different aftermarket stem to a Dahon, without it completely voiding the warranty on the rest of the bike?
What many people of the forum, who only know the Birdy from some pictures seen on the web, do not know is that unlike Dahon and almost all other bikes, the Birdy folding stem is not only a stem, it also includes the steerer tube normally part of the fork because the Birdy fork+stem implement an inverted Aheadset design with the steerer tube part of the stem instead of being part of the fork.

So, due to the specific design of the bike, no, you won't be able to mount another stem on the Birdy like due to the very clever front suspension design that doesn't dive when braking, you won't be able to mount another fork on the Birdy like to another very clever design you won't be able to mount another rear rack that folds automatically when the rear swing arm is folded.

For the maintenance of the Birdy, please look at the "SERVICE AND MAINTENANCE PLAN" stating at page 68 of the Birdy owners manual. You will see that there is an annual visual check of the stem planned.

All this meaningless discussion comes from the fact that Riese & Müller provides a very detailed owner manual instead of just nothing like many other bike brands do.
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Old 02-16-24, 12:50 PM
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Originally Posted by Jipe
you won't be able to mount another fork on the Birdy


...sure. That's why it's quite popular to do so in Asia.
So with less words - if the stem/steerer breaks, the fork comes off and the rider smashes with his head/face to the surface in front. That is a very clever improvement over uncontrollable riding under the wheels of a semi, if you use roadside bikeways. Ok under this point of view, the manufacturer is right replacing it frequently.
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Old 02-16-24, 01:40 PM
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Originally Posted by Jipe
All this meaningless discussion
To me it is not meaningless. You pointed out so many interesting details about this bike, it clearly rised my awareness of it and helped me to understand the concept. Thanks a lot and keep it up please!
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Old 02-16-24, 09:50 PM
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Originally Posted by Schwinnsta
The point is not so much about stiffness / flex per se, but that it is not so easy as to change the stem on the bike and be done with it as you seem to suggest. In this case, Zizzo, but many others the design fold and the stem design are integral. Yes there is some flex of the stem, but the stem is designed to fit between the halves, resulting in a better fold.
In my experience, the folding joints on stems are now rock solid. I perceived a *very slight* increased flex on the Dahon telescoping aluminum stem, versus my older fixed height steel stem, and not due to difference in material or fold, but only because, on the telescoping stem, very rigid bottom half, the top half is a lot smaller in diameter to fit/telescope into the bottom half, which tapers to a lot smaller at its top. The top end is an order of magnitude less section modulus (stiffness due to geometry), and it's held by a single-point clamp, so under bending moment, there can be slight movement, pivoting about the clamp area, and actual lateral movement deeper down, and this is what causes the slight squeak at that joint. That flex gets proportionally worse, the higher the stem is adjusted (top half extended), and I like it at max, I don't ride as low as I used to. But again, this amount of flex is well within acceptable levels. For that reason, I do prefer my older fixed stem, as I have townie shopping loads, so I like the greater rigidity when climbing with loads.

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Old 02-16-24, 10:17 PM
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Originally Posted by Jipe
What many people of the forum, who only know the Birdy from some pictures seen on the web, do not know is that unlike Dahon and almost all other bikes, the Birdy folding stem is not only a stem, it also includes the steerer tube normally part of the fork because the Birdy fork+stem implement an inverted Aheadset design with the steerer tube part of the stem instead of being part of the fork.

So, due to the specific design of the bike, no, you won't be able to mount another stem on the Birdy like due to the very clever front suspension design that doesn't dive when braking, you won't be able to mount another fork on the Birdy like to another very clever design you won't be able to mount another rear rack that folds automatically when the rear swing arm is folded.

For the maintenance of the Birdy, please look at the "SERVICE AND MAINTENANCE PLAN" stating at page 68 of the Birdy owners manual. You will see that there is an annual visual check of the stem planned.

All this meaningless discussion comes from the fact that Riese & Müller provides a very detailed owner manual instead of just nothing like many other bike brands do.
Interesting. A fair retort. I will investigate the design difference. I still think that critical structural components on consumer goods, should be designed robust, with a specific design margin of safety. But let me look at the design.

EDIT: OK I looked at the design, and it's exactly as I expected, based on your excellent discription. Yes, a steer tube projecting down, a fork that clamps around it (like a modern stem), and a... thrust cap(?) to adjust the bearing slack/preload. So... the clamped fork connection, that type is common on other areas of a typical bike, like modern stems, and handlebar clamps; You have clamping stress, and aft bending stress under braking loads. You also have forward loads due to the steering axis inclination and bike+rider weight. So not fully reversing loads, but reversing. I think the stress loads may be greater than at similar clamps of a stem and handlebar clamp. I'm not liking the looks of this joint; It's relying on material friction, but then so does a typical stem on top, but this area will be more highly stressed in moment so wants to bend open that clamp hole. I see in the pic only one clamp bolt, but the pic is from the bottom so could be obscuring a second bolt; Every modern clamped stem I have seen uses two clamp bolts and decent clamping length. On a joint like this, I would use at least two bolts, with (cross-drilled bolt heads, I can't think of the term) with stainless steel safety wiring between the two bolts in the direction of tightening both bolts, very standard in critical applications, and this is one of them. They're not talking about replacing the fork periodically, so that must be sufficiently robust. The concern is with that steerer tube, that's what they are worried about. You don't want a very thick-wall heavy tube for the entire length, the stresses drop drastically with increased distance from the fork. I would design it just like butted frame tubes, i.e., swaged to have greater wall thickness near end (constant outside diameter, reduced inside diameter near the fork), the full length of the fork clamp, and perhaps 1-2 cm above the bottom headset bearing. That would add very little weight, but be a lot more robust, and also resulting in the clamp design being more effective, because that depends on the radial stiffness of the tube. I'd use a premium steel with excellent strength but also toughness. Swaging the outside and inside of the tube end where it is thick, will result in a) tight tolerance, so more consistent clamp, b) increased material strength due to cold-working, c) residual compressive stresses on both inner and outer surfaces, for improved fatigue strength. Better. I've designed safety-critical joints like this, for mass-critical applications, designed for the life of the vehicle. It can be done, you just need to carefully finesse the details. And, after measuring or calculating worst-case loading, 10-occurance loads, etc, testing the parts with servo-hydraulic equipment in fixtures, to high-cycle fatigue tests, to validate the design. Also, I'd do an overload-bend test, to see the failure load, and failure mode; You want it to yield and deform, absorbing energy, push the front wheel back, but preferrably not completely fail (break-away), as that may make the difference between the wheel staying there and no crash onto pavement, or not.

Last edited by Duragrouch; 02-17-24 at 02:35 AM.
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Old 02-17-24, 03:12 AM
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The steerer tube is short, not longer than the one of a classic fork (it goes only till the folding hinge) and its a one piece machined item with thick walls that integrate the lower part of the stem hinge (the hinge is not soldered on a tube like for many folding bike stems) same for the upper part of the stem, also one piece machined item stem hinge+stem tube.

The design is identical to a Aheadset fork with two thick clamp bolt (on the side of the fork near the fork folding release lever) and one bolt in the classic Aheadset cap to adjust the bearing preload.

There was never any failure reported on the Birdy stem.

The Aheadset type of fork+stem mounting is the most used nowadays in the bicycle industry.
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