Dangerous failure on Dahon Speed P8

[highlandpark]

Yesterday I was riding rather slow when my Dahon Speed P8 handlepost port/hinge broke off! I ended up holding the detached handle bars in my hands like in a Buster Keaton movie.

I was extremely lucky that although there was car traffic on the street I managed to hop off the seat and stop safely.

The troubling thing is that The bike is 7 months old, has fewer than 30 riding days on it. I use it every now and then to commute to work, I avoid potholes, don't jump off curbs and weigh 170 pounds.

Has anyone experienced anything similar or it's just me who ended up with a defective part? I am really concerned and determined to find out if this could be a design flaw. I hope it was just a manufacturing defect.

[solution_63]

That's scary - glad you're OK.

[kb5ql]

Yesterday I was riding rather slow when my Dahon Speed P8 handlepost port/hinge broke off! I ended up holding the detached handle bars in my hands like in a Buster Keaton movie.

I was extremely lucky that although there was car traffic on the street I managed to hop off the seat and stop safely.

The troubling thing is that The bike is 7 months old, has fewer than 30 riding days on it. I use it every now and then to commute to work, I avoid potholes, don't jump off curbs and weigh 170 pounds.

Has anyone experienced anything similar or it's just me who ended up with a defective part? I am really concerned and determined to find out if this could be a design flaw. I hope it was just a manufacturing defect.

Looks like a defective stem. I had mine for two years with the older stem design (same alu principle), and never had a problem. Make sure you post in this thread as well :rolleyes:

Do Folding Bike Break in Half? (http://www.bikeforums.net/showthread.php?t=290190)

Glad you weren't hurt.

[spambait11]

Ouch! Good to hear you're ok. Don't know about a design flaw, but I've never been a fan of the alu handlebar post. Definitely post this in Dahon's forum as well.

Do you tend to pull back on the handlebars, by any chance?

[CrimsonEclipse]

HOLY CRAP!!!

You have my attention!!!

Did you report that to Dahon?

(now I'm afraid to rid my P8)
((I really go fast on mine))

CE

[Bacciagalupe]

I've put over 2,000 miles on my Mariner D7 and no hints of handlepost issues so far. But....

Dahon stems are very flexy. If you're pulling back on the bars all the time (e.g. when climbing, or standing in the saddle) you are likely to have a failure like that. But....

If you've only put a few hundred miles on it, though, I'd assume that's a factory defect.

[jur]

Whoa. Dahon will want to see this, I hope.

+1 on the alu post not being a good design.

[highlandpark]

Ouch! Good to hear you're ok. Don't know about a design flaw, but I've never been a fan of the alu handlebar post. Definitely post this in Dahon's forum as well.

Do you tend to pull back on the handlebars, by any chance?


I ride mostly on flat ground so there is not a whole lot of pulling on the handle bars going on. I didn't know the stem was made of aluminum until it broke. I thought it was steel. I contacted Dahon and they are interested in seeing the broken pieces but I didn't get a response like: "We'll give you a loaner until we repair and look into what happened." They told me to take it to a shop for a warranty repair.

I suppose when it gets repaired I will keep the handlepost as low as I'm comfortable in order to minimize lever effect on the joint. A good design feature would be to ensure that in case of separation there is some kind of semi-rigid connector inside the tube. Such device would minimize loss of balance so the rider would have a chance to apply breaks.

When my stem broke it felt that just a little connection between handle post and the frame would have improved my balance. I think the main thing is that when you find yourself holding detached handle bars your body has a tendency to straighten up and lose balance. You lose balance and that front wheel will turn to the side and you're toast.

[jur]

When my stem broke it felt that just a little connection between handle post and the frame would have improved my balance. I think the main thing is that when you find yourself holding detached handle bars your body has a tendency to straighten up and lose balance. You lose balance and that front wheel will turn to the side and you're toast.+1

When George Hincapie had that bad fall during the 2006 Paris-Roubaix, that's exactly what happened to him. (Oh and he wasn't riding a Dahon folder. :) )

[Bacciagalupe]

I ride mostly on flat ground so there is not a whole lot of pulling on the handle bars going on. I didn't know the stem was made of aluminum until it broke. I thought it was steel....
Material shouldn't make a big difference, it's just a question of weight & thickness. Even a steel handlepost, if made wrong or hit in the wrong spot, can fail.


I suppose when it gets repaired I will keep the handlepost as low as I'm comfortable in order to minimize lever effect on the joint. A good design feature would be to ensure that in case of separation there is some kind of semi-rigid connector inside the tube.
Again considering how little you've ridden it, it's a manufacturing issue, not a design issue. Plenty of people have put lots of miles on their Dahons without having this specific issue. Any bike can fail in numerous ways, and no frame-maker could afford to protect their bikes against every possible frame failure.

Handlepost height won't make a difference as long as the part is made right. It should be pretty easy for you to inspect the new one, just keep an eye on the inside and out before you ride. After awhile, you'll probably trust it again; if you don't, then get a Swift. The steerers on those suckers are Rock Solid.

Sucky Q&A on Dahon's part though, I'd say.


I contacted Dahon and they are interested in seeing the broken pieces but I didn't get a response like: "We'll give you a loaner until we repair and look into what happened." They told me to take it to a shop for a warranty repair.
Sounds about right to me... It would take as long for them to send you a loaner as for you to get a replacement part. If your LBS doesn't have the part, I'd get back on the phone to Dahon and get 'em to overnight the part to you.

Besides, nothing personal but this is a $550 consumer bike, not a $5,500 Orbea Orca used by a pro cyclist. :D

[fireworkz]

Yesterday I was riding rather slow when my Dahon Speed P8 handlepost port/hinge broke off! I ended up holding the detached handle bars in my hands like in a Buster Keaton movie.

I was extremely lucky that although there was car traffic on the street I managed to hop off the seat and stop safely.....

Two words come to mind ...
Lawsuit (Guess if you were injured) and Recall ! The latter especially i.e. if it is a defect for a particular model/year ! Dahon should be made aware of this as its also a Quality Control issue !

[highlandpark]

I live in Los Angeles. Dahon is local (although bikes are assembled overseas). They have the parts in stock. I dropped off the bike at the shop and they'll have it back on Monday "as good as new" as they said. Does that mean it will break after another 30 days of riding? I hope not.

[ekitel]

I was seriously considering a Dahon for a while, in spite of the 'made in china', my MacBook was shipped directly from China and has served me well in spite of the dark spots on the LCD screen, but talking with a sales dude at Bicycle Habitat in NYC made me change my mind, they used to be official Dahon dealers until recently and he said the reason was that one in four Dahons had warranty issues due to factory problems, it was at that point I decided to go with a Bike Friday instead.

in my business as a computer programmer there is a lot of concern over the issue of out-sourcing over-seas but more and more I hear from businesses that have been burned by unreliable asian programmers and have decided to shift their outsourcing needs back to domestic professionals who are motivated by the rewards of an above average living wage as opposed to subsistence/prison/slave wages. I think the same issues are involved in bicycle manufacturing and that sooner than later people around the globe are realizing that you get what you pay for. That doesn't mean that North Americans are better than Asians, it just means that people produce better products when they are paid fairly in a comfortable working environment....

[kb5ql]

You can review the labor policies of dahon by perusing this thread.

http://www.dahon.com/forum/index.php?showtopic=336&hl=factory

http://www.dahon.com/forum/index.php?act=attach&type=post&id=68

[Skidurts]

I was seriously considering a Dahon for a while, in spite of the 'made in china', my MacBook was shipped directly from China and has served me well in spite of the dark spots on the LCD screen, but talking with a sales dude at Bicycle Habitat in NYC made me change my mind, they used to be official Dahon dealers until recently and he said the reason was that one in four Dahons had warranty issues due to factory problems, it was at that point I decided to go with a Bike Friday instead.

in my business as a computer programmer there is a lot of concern over the issue of out-sourcing over-seas but more and more I hear from businesses that have been burned by unreliable asian programmers and have decided to shift their outsourcing needs back to domestic professionals who are motivated by the rewards of an above average living wage as opposed to subsistence/prison/slave wages. I think the same issues are involved in bicycle manufacturing and that sooner than later people around the globe are realizing that you get what you pay for. That doesn't mean that North Americans are better than Asians, it just means that people produce better products when they are paid fairly in a comfortable working environment....

i think you're drawing the wrong conclusions here. a fair wage afterall is relative to the local market and standard of living. product quality has a lot of other more important contributing factors: design, materials, quality control.

[CrimsonEclipse]

i think you're drawing the wrong conclusions here. a fair wage afterall is relative to the local market and standard of living. product quality has a lot of other more important contributing factors: design, materials, quality control.

I mean no disrespect guys, but let's keep this subject focused on the bike and the immediate
problem. The structural problem is immediate, we can save the world later.

sincerely

CE

[DaFriMon]

I live in Los Angeles. Dahon is local (although bikes are assembled overseas). They have the parts in stock. I dropped off the bike at the shop and they'll have it back on Monday "as good as new" as they said. Does that mean it will break after another 30 days of riding? I hope not.

I'm glad that you're getting such a quick resolution. If your experience had happened to me, I'd be pretty nervous about getting back on the bike. Still, I suspect that you were just tremendously unlucky about getting a defective part, while at the same time being rather lucky not to have a serious crash when it failed. With any brand, there has to be *some* chance of a catastrophic failure. If anyone has actual statistics on failure rates of different brands, it would be useful. Short of that, we're relying on individual anecdotes in forums like this.

All that said, that's a pretty horrendous defect, even if it was only one bike. Hopefully, Dahon will get to the bottom of what happened. It's in their interest to do so.

[highlandpark]

I wouldn't go as far to identify overseas manufacture as the sole reason for the problem. After all no one else has reported a similar issue in this and the official Dahon forum.

I purchase U.S. manufactured goods whenever I can. Sometimes they are better than their foreign counterparts and sometimes they are not. I'm no structural engineer but I you can tell that Dahons look and feel much better manufactured than off-the-mill Chinese bikes you can see at big box retailers.

[folder fanatic]

I wouldn't go as far to identify overseas manufacture as the sole reason for the problem. After all no one else has reported a similar issue in this and the official Dahon forum.

I purchase U.S. manufactured goods whenever I can. Sometimes they are better than their foreign counterparts and sometimes they are not. I'm no structural engineer but I you can tell that Dahons look and feel much better manufactured than off-the-mill Chinese bikes you can see at big box retailers.

I personally go by the 50% rule-of-thumb. I found that at least 50% of any manufactuered product from Asia (generally China) has some failure after a short period of time of using/owning. I am not saying that the product in question is bad. Far from it. It is just that. I bought 2 fans at the same time last summer. One quit after a couple of weeks use-simple domestic way of cooling a small room. The other is still operating fine. Same with both my Dahons. They both had defects. The Boardwalk with the front wheel assembly and the Piccolo with it's handle bar pin. While the bike shops that I bought them from both addressed them in their own ways, I still am amazed that these glaring examples of defective parts managed to slip through the bike shops to me. So I am grateful and relieved that you are not hurt.

[kb5ql]

I mean no disrespect guys, but let's keep this subject focused on the bike and the immediate
problem. The structural problem is immediate, we can save the world later.

sincerely

CE

Now that we know there is successful resolution to the OP's problem, let discuss the mythical man-month and how adding more people to a project does not make it finish any faster...

:D

[Polaris43]

I personally go by the 50% rule-of-thumb. I found that at least 50% of any manufactuered product from Asia (generally China) has some failure after a short period of time of using/owning. I am not saying that the product in question is bad. Far from it. It is just that. I bought 2 fans at the same time last summer. One quit after a couple of weeks use-simple domestic way of cooling a small room. The other is still operating fine. Same with both my Dahons. They both had defects. The Boardwalk with the front wheel assembly and the Piccolo with it's handle bar pin. While the bike shops that I bought them from both addressed them in their own ways, I still am amazed that these glaring examples of defective parts managed to slip through the bike shops to me. So I am grateful and relieved that you are not hurt.


I think your statistics are pretty far off. Otherwise, half the planes flying would fall out of the sky every day due to all of those defective Chineese parts. That's to say nothing of 50% of cars that should be broken down on the side of the road or all of the electronics (ipods, tvs, dvds, etc...) that should be crapping out according to your rule-of-thumb.

Perhaps it has more to do with what you paid for than where it was made... as in, you get what you pay for.

[invisiblehand]

I personally go by the 50% rule-of-thumb. I found that at least 50% of any manufactuered product from Asia (generally China) has some failure after a short period of time of using/owning. I am not saying that the product in question is bad. Far from it. It is just that. I bought 2 fans at the same time last summer. One quit after a couple of weeks use-simple domestic way of cooling a small room. The other is still operating fine. Same with both my Dahons. They both had defects. The Boardwalk with the front wheel assembly and the Piccolo with it's handle bar pin. While the bike shops that I bought them from both addressed them in their own ways, I still am amazed that these glaring examples of defective parts managed to slip through the bike shops to me. So I am grateful and relieved that you are not hurt.

C'mon ... the production process of just about every product crosses so many international borders that it makes this type of analysis quite difficult. The guys down the hall that do transfer pricing rip their hair out everyday trying to figure out the connections.

If you have a Mac (or any other computer) guess where it was probably made ... or at least a good fraction of the components. Ours is in Hong Kong at the moment being delivered here.

Anyway, I think that Polaris is on the money here. Anecdotally, stories from some friends at U. Maryland's Business School, there are factories in mainland China that specialize in low price and low quality production. But it is a pretty big country so I would be hesitent to overgeneralize. Remember that it wasn't that long ago when Japan was the center of "poor quality, cheaply made products" ... say 40 years ago.

Ok, enough of my rant. If this is over the top, my apologies folder fanatic.

EDIT: in bold.

[folder fanatic]

None needed, invisiblehand. I was simply trying to make sense of the cheap junk that is being shipped over here. It is mostly lots of little things, like the dress's cheap fabric that tore when my mother wore it-the first time. And not at the seams-but in the center of the fabric! Or the sorry lot of bikes being pushed at the local big box store. And the gizmo (adjusting nut) that won't stay tight in my newly replaced handlebars. It is not Chinese or Asian bashing. Just irritating little things done by some of the makers over there, over here-in the end it really does not matter. Yes, we are getting what we pay for no matter where the item in question is made. We seem to be declining in areas where it really counts.

[Skidurts]

It is not Chinese or Asian bashing.


Who said it was?


Just irritating little things done by some of the makers over there, over here-in the end it really does not matter. Yes, we are getting what we pay for no matter where the item in question is made.

Agree.

[charles vail]

Yesterday I was riding rather slow when my Dahon Speed P8 handlepost port/hinge broke off! I ended up holding the detached handle bars in my hands like in a Buster Keaton movie.

I was extremely lucky that although there was car traffic on the street I managed to hop off the seat and stop safely.

The troubling thing is that The bike is 7 months old, has fewer than 30 riding days on it. I use it every now and then to commute to work, I avoid potholes, don't jump off curbs and weigh 170 pounds.

Has anyone experienced anything similar or it's just me who ended up with a defective part? I am really concerned and determined to find out if this could be a design flaw. I hope it was just a manufacturing defect.

I have one word.........Aluminum!

Sorry but......This is why I will only buy a Bike Friday with a steel stem and a normal length steel seat tube with no super long flexy aluminum seatposts or stems.

[keithnyc]

Yesterday I was riding rather slow when my Dahon Speed P8 handlepost port/hinge broke off! I ended up holding the detached handle bars in my hands like in a Buster Keaton movie.

I was extremely lucky that although there was car traffic on the street I managed to hop off the seat and stop safely.

The troubling thing is that The bike is 7 months old, has fewer than 30 riding days on it. I use it every now and then to commute to work, I avoid potholes, don't jump off curbs and weigh 170 pounds.

Has anyone experienced anything similar or it's just me who ended up with a defective part? I am really concerned and determined to find out if this could be a design flaw. I hope it was just a manufacturing defect.


Can you do me a favor and post this on dahon's message board? Here's the link:
http://www.dahon.com/forum/index.php?showforum=5

I'd be interested to see thier responses.....The members (as well as the Dahon tech support folks) are a great group and they may benefit from this.

[Polaris43]

I have one word.........Aluminum!

Sorry but......This is why I will only buy a Bike Friday with a steel stem and a normal length steel seat tube with no super long flexy aluminum seatposts or stems.


Does this mean that you don't fly on those super flexy aluminum airplanes?

[charles vail]

Does this mean that you don't fly on those super flexy aluminum airplanes?

I don't fly.......plus its not the same comparison. Airplanes are a totally different structure with a framework and skin etc. A long aluminum tube with a weight causing it to flex will eventually crack the alumuinum since there is a limited amount of fatigue cycles with aluminum. Airplanes are inspected and grounded when they don't meet safety standards....we hope. In the case of the Dahon I suspect that the part was defective since it had so little use. I just prefer a steel stem and frame tube that is long enough to avoid the extreme flex that a long aluminum seatpost or stem would be subjected to. I am a heavy rider and that amplifies the effect even more. The Swift and Bike Friday designs are better IMHO from a durability standpoint.

[CrimsonEclipse]

Does this mean that you don't fly on those super flexy aluminum airplanes?

I have yet to fly in a plane that transports 5-10 times it's weight through constant extreme turbulence.

Not to mention, if they were certified to the same standards, they'd cost $50,000 each

CE

[CaptainSpalding]

. . . . A long aluminum tube with a weight causing it to flex will eventually crack the alumuinum since there is a limited amount of fatigue cycles with aluminum.
Beg pardon, but these generalizations seem a bit hasty to me. For example, you seem to imply that steel has an unlimited amount of fatigue cycles. (That would be wrong.) It is true that the fatigue characteristics of steel and aluminum differ, but to say that any aluminum part is inferior to any steel part is to take a buzz word like "fatigue cycle" and build a grossly oversimplified fantasy around it. There are many dimensions to the fatigue cycle. Frequency, amount of flex, etc. The fatigue characteristics of aluminum are well known and engineers factor them into their designs. Aluminum bicycle components have been around for decades and proven themselves reliable.

I have no doubt that the situation of this broken handlepost is not a design issue, but a manufacturing defect. The photos provided are on the small side, but I believe I can see some crystalizing in the weld. This could indicate an interruption in the flow of shield gas, or an impurity in the metal of the component or the welding rod which contaminated the weld.

[geo8rge]

The Mast style steering tubes are not a good design. There is too much bending stress at the base, think if it as a lever. Birdy has also had failure problems. Making the things out of Al makes the design worse.

As to aircraft, they are inspected regularly by skilled mechanics with specialized equipment. I try to inspect my Birdy before riding, but cannot be sure I will catch a crack.

[charles vail]

Beg pardon, but these generalizations seem a bit hasty to me. For example, you seem to imply that steel has an unlimited amount of fatigue cycles. (That would be wrong.) It is true that the fatigue characteristics of steel and aluminum differ, but to say that any aluminum part is inferior to any steel part is to take a buzz word like "fatigue cycle" and build a grossly oversimplified fantasy around it. There are many dimensions to the fatigue cycle. Frequency, amount of flex, etc. The fatigue characteristics of aluminum are well known and engineers factor them into their designs. Aluminum bicycle components have been around for decades and proven themselves reliable.

I have no doubt that the situation of this broken handlepost is not a design issue, but a manufacturing defect. The photos provided are on the small side, but I believe I can see some crystalizing in the weld. This could indicate an interruption in the flow of shield gas, or an impurity in the metal of the component or the welding rod which contaminated the weld.

Yes and no.......I'll take a steel stem over any aluminum one, providing, as you say, the weld is done right.
The weight limits imposed on many of these folders with tall stems and seatposts tells me something. A heavy rider like myself would prematurely fatigue one of these aluminum pieces in short order. Its not like the "fistfull of post", like on a classic designed bike, where you get virtually no flex. A shorter section of seatpost supported by steel and a steel stem makes alot more sense to me. I am aware of the engineering that goes into making different materials work, for their intended purpose but you have to admit a steel tube of adequate guage is going to last way longer than aluminum, unless it is very overengineered and still, its aluminum and if it flexes too much, it will break. How many springs are made of aluminum? ;)

[CaptainSpalding]

. . . The weight limits imposed on many of these folders with tall stems and seatposts tells me something. A heavy rider like myself would prematurely fatigue one of these aluminum pieces in short order.
The determining factor on the weight limit of folders is the strength of the frame joint.

How many springs are made of aluminum?
Got me there. No springs that I know of that are made out of aluminum. But as I understand it, bikes are not springs. There are plenty of bikes made out of aluminum, though. Plenty of cars. Plenty of aircraft. . . ;)

[CrimsonEclipse]

Also, when was the last time you saw an aluminum fork?

I prefer steel to ALL other materials for a bicycle for its failure mode.
It usually gives you a warning.

CE

Dear Dahon, when you make a steel stem replacement, please let me know.

[charles vail]

The determining factor on the weight limit of folders is the strength of the frame joint.

I know what you are saying but.......in the case of folding bicycles, the weak points are the overly long (compared to standard bikes) seat post and stem. When these get long they flex, kind of like a spring! In fact this has been the reason many give for the soft ride of folders, since the wheels are so unyealding. All that flexing eventually leads to failure, where as a steel part can take the flexing longer (like a spring). What makes aluminum survive, is the fact that it is often over engineered to limit flex. Steel forks are actually springs that soak up bumps as I'm sure you have seen when riding a steel bike, the forks move. Of course, if they move too far, they bend and stay bent. Aluminum on the other hand when bent will crack alot sooner. This is why experienced bicycle mechanics suggest replacing handlebars and even stems that get alot of use. Handlebars flex (like a spring) and the aluminum eventually fatigue cracks,especially if it gets scratched or gaffed for a lack of a better term.

Got me there. No springs that I know of that are made out of aluminum. But as I understand it, bikes are not springs. There are plenty of bikes made out of aluminum, though. Plenty of cars. Plenty of aircraft. . . ;)

I suppose a bicycle can be made of aluminum that won't fail if it never gets flexed beyond its limits. Steel in the common guages just seems easier to build into long lasting frames. If I could get nice slender or hollow stainless steel cranks I would in a heartbeat. Stems, bars and seatposts are available as well as titanium and I'd just about bet a bicycle could be made to weigh nearly the same as a bike with aluminum parts. The trouble is the manufacturing costs would prohibit that. Since steel is harder on tooling.

[jur]

Dear Dahon, when you make a steel stem replacement, please let me know.The cheaper Dahons come with a steel handlepost.

[CrimsonEclipse]

The cheaper Dahons come with a steel handlepost.

Telescoping?
Directly swappable?

CE

[highlandpark]

The matter got resolved. I haven't had time to write.

Safety Cycle in Los Angeles replaced the stem. Since Dahon is local the owners of SC have a very good relationship with Dahon, got the part in the next day and got me on the road again. The new stem looks a bit different then the old one. I hope it's better!

[CrimsonEclipse]

how is it different?

CE

[highlandpark]

I'm writing from memory. It has a different latch and the shape is thicker. There may be few other things.

[keithnyc]

highland-
Just curious...did they charge you for the new piece or only the labor costs? I thought the Dahons had a lifetime warranty on the frame. thanks and happy riding.

[pm124]

Briefly had a bike with the steel Dahon stem. It weighs a ton, but is strong. No, it's not at all adjustable.

I'm no engineer, but I'm with Sheldon Brown on the aluminum versus steel thing. It's a bit silly. Anything that is made improperly (Dahon has tons of posts of stems breaking) will break no matter what it's made of. The aluminum stems that are adjustable in the midline flex like mad. I would never buy a bike with one of those on there. And, if I remember my Physics 101 correctly, steel is highly subject to metal fatigue.

In fact, I was just riding with a guy yesterday whose Bike Friday frame cracked in half. He said that he sent it back to the factory, and they welded it, only to have it crack again.

Of the two Birdy stem breaks, one was on a 1997 Elox and I believe the other was on Chop!'s Birdy red. (Chop! are you out there to confirm?) Given that the latter bike was sawed and welded like crazy it may have been damaged. Damn, I read too many of these things. Back to work.

[highlandpark]

highland-
Just curious...did they charge you for the new piece or only the labor costs? I thought the Dahons had a lifetime warranty on the frame. thanks and happy riding.


They didn't charge me for either. To be totally fair, Dahon was very quick to respond. It certainly helped that they had the part in stock at their main office. Eric from Safety Cycle in Los Angeles where I bought the bike picks up part from Dahon regularly so the whole repair was done in 2 days.

Speaking about Eric and his shop I have to say that they treated me really well. They went above and beyond with this. After I picked up the bike I realized that the new stem design has a rivet in a bad place and it scratched my frame. I went back to Eric for help and he spent a bunch of time trying to resolve it. They also ended up replacing a break cable and a cracked basket all free of charge.

[1oddmanout]

yeah, the post on the newer P8s scratch the frame - mine's got an ugly cut in it. Until Dahon recalls (any smileys on this forum, like one that says 'yeah, right' with maniacal laughter?) these 2-piece posts and replace them with a solid design, I put a sticker over the part; it's getting damaged as well.

[folder fanatic]

I own 2 Dahons. Both have steel frames. Except for the fact that the handebars/stem are made from different metals. My old Boardwalk has a one piece steel stem. That bike is heavy, but very solid. I never had any issues or problem with the stem-just the front wheel at purchase. The Piccolo is another matter. It's stem is a two piece one made of aluminum. I don't have a issue with flex, since I am quite light and I do not pull up or something similar on the stem. But I do have to use Red Loc Tite to keep the adjustable nut in the stem's base from not moving every time I fold the bike. I tend to ride very upright on both so that should not be too critical in causing flexing or quickly loosening nuts. I think there is a real compromise with choice (if there is one) of the different styles or makes of handlebars/stems.

[awagner]

I own 2 Dahons. Both have steel frames. Except for the fact that the handebars/stem are made from different metals. My old Boardwalk has a one piece steel stem. That bike is heavy, but very solid. I never had any issues or problem with the stem-just the front wheel at purchase. The Piccolo is another matter. It's stem is a two piece one made of aluminum. I don't have a issue with flex, since I am quite light and I do not pull up or something similar on the stem. But I do have to use Red Loc Tite to keep the adjustable nut in the stem's base from not moving every time I fold the bike. I tend to ride very upright on both so that should not be too critical in causing flexing or quickly loosening nuts. I think there is a real compromise with choice (if there is one) of the different styles or makes of handlebars/stems.

Just thought I'd second the reccomendation to use thread lock on the nut that controls the tightness of the handlebar latch. The nut kept working loose on my Speed P8 until I requested that my mechanic hit it with some thread lock. Problem solved so far.

I'm really surprised the OP's stem failed where it did. I imagine my stem failing in the internal sliding locking thing.

[EvilV]

Funny thing is, well made steel bikes with those fancy steel alloy tubings made by Reynolds in England are very light and strong. The bikes feel light and springy too. As I recall, the tubes are swaged in some way to make them thicker at the ends where they are joined. My alu bikes are easily as heavy as the expensive steel ones I used to have. Of course we've all tried to pick up crude, heavy steel bikes made out of old girders and scrap iron, but they are usually dirt cheap, and that's not the market we're talking about.

I'm coming around to favour quality steel frame construction, partly because it has a longer life and is easily repaired should repair be needed. Also, as someone mentioned above, when it does fail, it normally does so more slowly than aluminium.