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-   -   Tern Link - Catastrophic failure of Frame Hinge Bolt (https://www.bikeforums.net/folding-bikes/1101978-tern-link-catastrophic-failure-frame-hinge-bolt.html)

Bonzo Banana 08-10-17 01:53 AM


Originally Posted by smallwheeler (Post 19780729)
what would it take? multiple deaths? i'm sure you realize it's only by amazing luck that that hasn't already occurred.

Maybe I'm wrong in assuming this but it always feels to me that people take little notice of the weight restrictions on bikes. You get a Specialized bike that has a weight capacity of 136kg/300lbs and lifetime frame warranty and you get a Decathlon BTwin bike that has a load capacity of 100kg which they state includes the bike weight itself which could be 15kg.

http://www.btwin.com/notices/wp-cont...5V_EN_PE12.pdf

So one is about 85/86 kg capacity in real terms and the other is 50kg stronger a huge difference. Of course the btwin bike gets the good reviews thanks to its super light design and low price and the Specialized looks expensive and handles poor in comparison but is actually a much stronger and safer bike. There has been a huge recall of Btwin bikes recently due to frame failures for larger frame sizes of their mountain bikes and I wonder how many of those people were actually within their low weight requirements especially as people tall enough to need the larger frames would be likely to be over the bike's low weight limits.

If a Tern bike has a 95kg or 105kg maximum weight capacity allowing for clothes and things I might want to carry I'm going to need a body weight of maybe 80 or 90kg to be safely in their maximum weight capacity. I realise these Tern frames may actually have failed due to quality issues and inconsistency of manufacturing but assuming they have born the cost of this recall and have improved their bike frames now plus working within their weight limits I would think they would still be a viable option. Sadly the very best weight I've achieved in recent years is about 95kg and I'm aiming to get to 100kg at the moment as I'm north of that figure. I'll probably always be too heavy to be safe on a Tern bike anyway. One thing I won't be buying is a secondhand Tern bike, not knowing its history and who has been riding it yet I actually see the secondhand price of Tern bikes is actually really high.

Mark Bickerton 08-10-17 04:07 AM


Originally Posted by downtube (Post 19781074)
This sounds kind of like IBM, Google or Apple. However, the truth is the IP they used against me was worthless since no one ever used anything like it in the bicycle industry. It was developed by Dahon ( patent was submitted and approved for Dahon ). They hold a couple design patents ( design IP is nearly impossible to enforce ), especially when no one uses such poor designs. It didn't stop them from filing a case for patent infringement. Every lawyer I talked to laughed at the claim.....it was that ridiculous. I understand these cases have been filed against more companies than mine. I know of one overseas that conceded to the Plaintiff's demands...without a fight. I have been told there are many more.

Thanks,
Yan

Yan,

I doubt either Dahon or Tern would have wasted money on expensive lawyers persuing frivolous claims.

Mark

downtube 08-10-17 07:28 AM

Mark,

I think your presence is best served in a heavily moderated forum like Tern's. People are free to speak here.

Well the complaint can be found at https://www.dropbox.com/sh/x5ddjbzrk...pofuUT-Sa?dl=0 . I also included the warning letter that was sent to my "fake" address in Agora Hills, Ca . More on that later.

There are many problems with the complaint:

1. Jurisdiction - I have not lived or operated the Downtube in PA for nearly a decade, yet it was filed in PA. www.downtube.com even states we are in Greensboro, NC and I deliver bikes in the Triad.
2. There are claims of shell businesses - This is beyond absurd. Who would even think of such nonsense??? Is there any justification? If so please share.
3. They claim we don't have the capital to run our operation- I've been doing this for almost fifteen years, and we have had triple digit growth in the past few years. I would say our operation has never been better.....but what do I know???
3. The complaint claims that I was served with a warning letter. A letter was sent to me at a fake address in Agora Hills, Ca. I have never set foot in the city of Agora Hills, Ca. The address was a UPS Store Box. I called the store and they confirmed that I never owned a box at the store. The filing attorney stated he got the address from the Plaintiff ( Mobility/Tern ). The filing attorney may have issues with the BAR since I was never served the letter & the complaint claims I received it. They are not allowed to lie in a complaint, my being served with a warning letter was a lie!
4. Then we get to the design patents- Every attorney laughed at the claim. They all said the same thing, " we don't see any connection". It was that ridiculous.

They pulled the case case after I threatened Rule 11 sanctions, which applies to filing a frivolous lawsuit.

To summarize Downtube beat Mobility ( Tern ) and it will happen again next time they file more nonsense.

Thanks,
Yan

Blackstrida_A_ 08-10-17 08:34 AM

I mean that Mr. Bickerton's appearance here deserves thankfulness, appreciation and respect - but not being attacked for things which may not be mainly his mission at Tern.
Please let us get back on topic, regarding the hinge bolt.
(I do not own a Tern bike.)


Originally Posted by audioforma
Any suggestions please? I bought this bike second hand...

As this is your first post:
Welcome at bikeforums :)

I believe to remember that Tern's warranty is valid for the first buyer exclusively,
in that case you might think about consulting skilled bike mechanics.
Explain them the facts, show them pic and tools description below - they will know how to use the extractor if they are really skilled!

1. We, two experienced Viennese mechanics, claim that it is shameful and awkward to hear bike store owners say:
"OMG - a snapped bolt thread - this is a total frame loss!"
Repairing of threads and retracting of broken bolts is actually basic knowledge for a bike mechanic - we recommend to hire qualified personnel.
Replacing the frame for this reason is a tremendous waste of ressources we believe.

2. The broken Tern bolt - granted - may be called tricky, but it is possible to repair and my friend figured out how, as already posted at a German forum. For an experienced mechanic it should be no problem to fix the issue within 1-2 hours - providing that correct tools are used; these are very important.
Below the "special" tools; costs ~ 20 Euros, and a short description:
Most right a cylindrical (screw) extractor pin, size1, Ø 3,2 x 60 mm (it is rippled lengthwise),
Ausdrehstift Gr.1 3,2X60mm bei SPIRAL Reihs & Co. KG
next to it the nut for driving of the pin (the hole inside is also rippled to match the outer shape of the pin exactly),
Ausdrehmutter Gr1 10X3,2mm bei SPIRAL Reihs & Co. KG
above the guiding tube for the Ø 3,2 mm drill bit (size Ø 8,0 x Ø 3,2 x 30 mm, edge beveled),
a few high quality Ø 3,2 mm drill bits,
most left the new Tern bolts.
Hint: Don't waste time with the common, conical, left-hand threaded screw extractors, these will most likely not work.
http://i769.photobucket.com/albums/x...ternkitbyM.jpg

Abu Mahendra 08-10-17 09:50 AM


Originally Posted by smallwheeler (Post 19780724)
you forgot the dahon "lapdogs"?

Those exist too. Blind fanboyism, dogmatic allegiance exists in all brands. I, myself, love my two Dahons, but admittedly they are not the common, entry-level ones. The moment Dahon started pulling T**n antics, I would call it out for what it is. Dahon lapdogs are far less common and numerous than, say, Brompton or BF...

HGR3inOK 08-10-17 03:02 PM


Originally Posted by Mtroup (Post 19776784)
As a new Tern owner, I find it valuable to have a Tern rep visiting these forums. He stepped up to resolve a problem to the customer's satisfaction, and is harassed and baited for his attention. If for some unfathomable reason, you need to hate on a company (a company of which you are clearly not even a customer), maybe you could at least pretend to be civil, or better yet, ignore the thread, so that us actual customers can benefit from the rep's presence on the forum. Thanks.

Please note that I am Senior Member of this forum who reviews forum postings daily, and a former authorized dealer for Tern (and Dahon, Raleigh, Diamondback, Hoffman, Linus and Detroit Bikes).

As an authorized dealer for Tern bicycles in the USA from 2011 through 2015, my experience was that the company owners and employees were conscientious, accessible and focused on providing the best folding bikes possible. Frame recalls were handled promptly with a focus on minimizing the inconvenience to the customer. My recollection is that we only had one Tern warranty claim (a broken brake lever?), and that claim was handled promptly and satisfactorily.

I agree with Mr. Lyansky's statement, "There is a lot you may not be aware of." I do not agree with his position regarding Tern to the extent that he portrays the company and its employees as evil beings who do not care about their customers.

-HANK RYAN-
Norman, Oklahoma USA

Abu Mahendra 08-10-17 04:03 PM


Originally Posted by HGR3inOK (Post 19783054)
Please note that I am Senior Member of this forum who reviews forum postings daily, and a former authorized dealer for Tern (and Dahon, Raleigh, Diamondback, Hoffman, Linus and Detroit Bikes).

As an authorized dealer for Tern bicycles in the USA from 2011 through 2015, my experience was that the company owners and employees were conscientious, accessible and focused on providing the best folding bikes possible. Frame recalls were handled promptly with a focus on minimizing the inconvenience to the customer. My recollection is that we only had one Tern warranty claim (a broken brake lever?), and that claim was handled promptly and satisfactorily.

I agree with Mr. Lyansky's statement, "There is a lot you may not be aware of." I do not agree with his position regarding Tern to the extent that he portrays the company and its employees as evil beings who do not care about their customers.

-HANK RYAN-
Norman, Oklahoma USA

How many Tern folders are sold in OK?

HGR3inOK 08-10-17 05:11 PM


Originally Posted by Abu Mahendra (Post 19783222)
How many Tern folders are sold in OK?

I don't know. We were selling ~1/month when we had our shop in Norman. Our best seller was the Link C7 (~1/3 of the Terns we sold). We drew folding bike customers from Kansas, Arkansas and Texas because we had one of the largest selections of folding bikes between the Mississippi and the Rockies.

-HANK RYAN-
Norman, Oklahoma USA

Snoraa 08-14-17 12:47 AM


Originally Posted by Mark Bickerton (Post 19773263)
Hi Alex,
I am sorry to hear that you are disappointed in your Tern bike and the service you have had.
If you think I can be of any help please email me directly and I will do what I can.
My email is "mark . bickerton @ ternbicycles . com" (no spaces)
Thanks
Mark Bickerton
UK Representation for Tern Bicycles

Mark
I wasn't disappointed with my bike, I thought it was an extremely good and fast bike! But you know, when you are riding at 18mph + and the next thing you know you are on the floor only to find your bike has just snapped in half you kind of lose confidence in the brand you bought into!!
Evans customer service had been very good to date!

dahoneezz 08-14-17 08:04 AM

The Tern Verge has similar geometry to the Dahon IOS no? Are there any cases of this particular Dahon breaking? Wonder what is the difference between the two ...

dahoneezz 08-14-17 08:11 AM


Originally Posted by Blackstrida_A_ (Post 19781908)
I mean that Mr. Bickerton's appearance here deserves thankfulness, appreciation and respect - but not being attacked for things which may not be mainly his mission at Tern.
Please let us get back on topic, regarding the hinge bolt.
(I do not own a Tern bike.)



As this is your first post:
Welcome at bikeforums :)

I believe to remember that Tern's warranty is valid for the first buyer exclusively,
in that case you might think about consulting skilled bike mechanics.
Explain them the facts, show them pic and tools description below - they will know how to use the extractor if they are really skilled!

1. We, two experienced Viennese mechanics, claim that it is shameful and awkward to hear bike store owners say:
"OMG - a snapped bolt thread - this is a total frame loss!"
Repairing of threads and retracting of broken bolts is actually basic knowledge for a bike mechanic - we recommend to hire qualified personnel.
Replacing the frame for this reason is a tremendous waste of ressources we believe.

2. The broken Tern bolt - granted - may be called tricky, but it is possible to repair and my friend figured out how, as already posted at a German forum. For an experienced mechanic it should be no problem to fix the issue within 1-2 hours - providing that correct tools are used; these are very important.
Below the "special" tools; costs ~ 20 Euros, and a short description:
Most right a cylindrical (screw) extractor pin, size1, Ø 3,2 x 60 mm (it is rippled lengthwise),
Ausdrehstift Gr.1 3,2X60mm bei SPIRAL Reihs & Co. KG
next to it the nut for driving of the pin (the hole inside is also rippled to match the outer shape of the pin exactly),
Ausdrehmutter Gr1 10X3,2mm bei SPIRAL Reihs & Co. KG
above the guiding tube for the Ø 3,2 mm drill bit (size Ø 8,0 x Ø 3,2 x 30 mm, edge beveled),
a few high quality Ø 3,2 mm drill bits,
most left the new Tern bolts.
Hint: Don't waste time with the common, conical, left-hand threaded screw extractors, these will most likely not work.
http://i769.photobucket.com/albums/x...ternkitbyM.jpg

I assume the bolt breaks at interface of threaded part and non-threaded part?

Then you drill using the guide? Next you hammer the extractor pin and screw out the broken threaded portion of the bolt?

Sorry, based on the picture, I am trying to guess the method.

With regard to the "reverse thread" conical extractor, yes I had bad experience with it, but it was with a car engine. In the end, had to weld a metal piece to broken bolt to remove it.

Blackstrida_A_ 08-14-17 09:51 AM

Hi dahoneezz,

no reason to be sorry and three times "Yes exactly" :)

Two more hints for drilling/using guide:
- The guide can be used at the same time for the depth adjustment of the drill bit.
- The borings (or drill shavings, swarfs) should be removed several times during drilling.

masch 09-26-17 07:22 AM

Heya! Thanks for these replies. Where can I get this tool set from? [Picture in post #80 - can't reattach the picture because forum requires me to have at least 10 posts first]

In the link you've provided (thanks) only the right-bottom tools were there but not the drill bits (I assume they're designed for the bolt).

My wife has just had a frame failure while crossing across a traffic light at relatively high speed (~10-15kmh) and the frame just broke and she jumped off the bike just in time to run across the other side while other cars braked to let her pass. The bolt, like others have said in this thread, broke off at the section between the threaded part and the outer part. We couldn't find the outer part on the road and it was dark. Have ordered the replacement bolts and the washers but can't seem to get the broken off threaded part out even with screw extractors.

Just before reading this thread, I have been thinking of just cutting the new bolt out at the threaded bit with boltcutters and then taping the bolt in or pouring in liquid rubber to keep it permanently inside.

If you have a link to where we could get these tools, please assist :) Thank you. (especially looking for the right drill bit guiding tube & the drill bit itself - there are two drill bits in the picture, what are they for?)

Blackstrida_A_ 09-26-17 09:18 AM


Originally Posted by masch
...she jumped off the bike just in time to run across the other side while other cars braked to let her pass.

:eek:
But at least was your dear wife not at all injured as far I understood?

Please simply disregard the longer drill bit and sorry, this is not a kit (Imagename misleading), most of the tools were collected at our local tool stores.
Maybe we can help you better to find local sources if you tell us where you live?
Just the guiding tubes were home made with a turning lathe, out of silver steel at the pics (these are intended for multi-use at a workstore).
But I think one could use, especially for single time use, even aluminium tubes - the material doesn't matter.
Guess your local locksmith, turnery, car workstore could create such a thingy for a few Euros?

Regarding drill bit: You just want a high quality 3,2 mm drill bit, preferably those with that mostly golden, titanium-nitride coatings.
The drill bit must be long enough to reach through the complete broken piece (A) while leaving the other end also long enough to be clamped hard into the drill chuck (B). Below shown is 65 mm - it shouldn't be shorter than that.

Very important is to remove the burrs several times during and after the drilling process.
Compressed air is here very helpful - but please save your eyes by all means!

...and as this is your first post:
Welcome to bikeforums.net :bike:

http://i769.photobucket.com/albums/x...rnkitbyM02.jpg

masch 09-26-17 09:34 AM

Hi, thanks for the reply.


But at least was your dear wife not at all injured as far I understood?
Yes physically she is all okay, but the trauma hasn't fully gone away yet, if ever.



Ah yes, I was mainly intrigued with the guide tube because that would help me really centre on the hole. I think the outside is 8mm and the threaded part is 5mm? I'm not sure.

Somebody sent me a private msg but I couldn't open it because

The administrator has restricted use of the private message system to members with less than 10 posts.
.

To the person, could you leave a comment on my youtube channel? I'll drop my contact info there.

(oh crap, I am not allowed to post URL either)

Suggestion: search YouTube for maschkisiel and click Discussion tab

smallwheeler 09-26-17 11:07 AM

let me get this straight - your wife nearly gets killed when this piece of garbage snaps in half now you're just going to cheerfully repair it yourself?

you're taking advice online from someone who claims "Replacing the frame for this reason [because the bolts broke]is a tremendous waste of ressources".

not returning this bike and demanding your money back is the real "waste" for the simple reason that you are letting the manufacturer off the hook for their criminally shoddy product.

HGR3inOK 09-26-17 12:56 PM


Originally Posted by masch (Post 19887807)
... My wife has just had a frame failure while crossing across a traffic light at relatively high speed (~10-15kmh) and the frame just broke ...

What is the make and model of the bicycle? And how old is it?

-HANK RYAN-
Norman, Oklahoma USA

Blackstrida_A_ 09-26-17 12:56 PM

So guys, sorry, I'm not able to contribute to a moralic-criminal discussion about wifes or ressources,
therefore I'm out if that does not stop.

As the title says - we were talking about one broken bolt :wtf:

And smallwheeler; could you please be so kind to respect my meaning just as I do respect yours?
Thanks in advance.

masch 09-26-17 01:19 PM


Originally Posted by smallwheeler (Post 19888414)
let me get this straight - your wife nearly gets killed when this piece of garbage snaps in half now you're just going to cheerfully repair it yourself?

not returning this bike and demanding your money back is the real "waste" for the simple reason that you are letting the manufacturer off the hook for their criminally shoddy product.

My wife won't ride it anymore. I was riding a public bike and she was using my bike. I'll just be using that bike from now on. I don't have any other choice really. One may have more choices if you have the money. Even just to get it fixed I'm not sure if I can spare much. Will look towards a different model once I finish my studies for sure but until then will have to make do with what we have.


Originally Posted by HGR3inOK (Post 19888695)
What is the make and model of the bicycle? And how old is it?

It is a Tern Link C7. I am not sure what year, it is probably 4 years old but I only got it earlier this summer. It is not the bike itself that broke but the one or two frame bolts (as in pics above) - the bolt must have cracked in between the threaded part and the load bearing part. The load bearing part has no damage or dents, it is holding in its place with a masking tape (and an old cigarette butt) for about 2 weeks now but this morning the tape has come off a little and I'm trying to look for a more permanent fix (or at least something that would hold out a bit longer) and that's how I found this website.

bargainguy 09-26-17 04:29 PM

If you go to the Intro section and say hello to seven of your new friends by posting in their posts, you get to the 10 post minimum to get PMs, post pix and the like.

dahoneezz 09-26-17 06:35 PM


Originally Posted by Blackstrida_A_ (Post 19888130)
:eek:
But at least was your dear wife not at all injured as far I understood?
(Snip...)
http://i769.photobucket.com/albums/x...rnkitbyM02.jpg

I think there is big stress concentration at the interface to threaded part. Abrupt change in the section modulus (and the change is not linear).

A better solution would be to use a proper hinge pin all the way through so that you have a solid cross section resisting the bending, none of the threaded portion. This is a design flaw.

sweeks 09-26-17 08:04 PM


Originally Posted by dahoneezz (Post 19889453)
A better solution would be to use a proper hinge pin all the way through so that you have a solid cross section resisting the bending, none of the threaded portion.

This change has been made. My Verge S11i received a frame replacement under a recall over a year ago. The pivot in the redesigned frame hinge is a single rod retained by set screws.

It sounds like the bike was purchased used, so the owner may not have been notified of the recall if his bike was among those identified as being potentially affected.
Steve

dahoneezz 09-26-17 08:18 PM


Originally Posted by sweeks (Post 19889596)
This change has been made. My Verge S11i received a frame replacement under a recall over a year ago. The pivot in the redesigned frame hinge is a single rod retained by set screws.

It sounds like the bike was purchased used, so the owner may not have been notified of the recall if his bike was among those identified as being potentially affected.
Steve

There is a recall due to hinge bolt issues? I thought the recall was for frame/hinge welding issue? Hinge bolt recall should be a whole lot of bikes no? Pretty easy to check. :D

sweeks 09-26-17 08:51 PM


Originally Posted by dahoneezz (Post 19889622)
There is a recall due to hinge bolt issues? I thought the recall was for frame/hinge welding issue? Hinge bolt recall should be a whole lot of bikes no? Pretty easy to check. :D

You are correct. The recalls, AFAIK, were for the weld problem, which has also been corrected. I noticed the redesigned pivot in the replacement frame, which was recalled for a potential weld defect. Sorry for any confusion.
Steve

EDIT: I had lumped the bolt problem in with the weld problem in my mind... they're kind of in the same area. I just looked on the Tern site's "Product Alerts/Recalls", and it's only the weld problem that was the reason for the recalls.

Bonzo Banana 09-27-17 03:56 AM

I'm unsure how recalls work in other countries but in the UK I think for many recalls it doesn't matter if you are the original purchaser. Is there any chance the frame may be one of those recalled and will get a replacement frame whatever the state of the hinge?


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