Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Folding Bikes Discuss the unique features and issues of folding bikes. Also a great place to learn what folding bike will work best for your needs.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 03-21-17, 09:04 AM   #1
EdEllis
Newbie
Thread Starter
 
Join Date: Mar 2017
Bikes:
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Tern Link - Catastrophic failure of Frame Hinge Bolt

Hi. I purchased a Tern Link in December 2016. About 2 weeks ago the frame became wobbly. I noticed that one of the two frame hinge center bolts had sheared. Half of the bolt in the frame the other on the floor..
I took it back to the the dealers, who in turn called the suppliers. The suppliers Palegon in the UK wanted nothing to do with it. The dealer took it to a work shop and had the bolt drilled out, but in so doing stripped the thread.
Tern did not respond apparently.
I insisted on my money back. Nobody would offer any technical reason why the bolt failed, nor would they offer any guarantee that that the other bolt would not fail, nor that the repair wouldn't fail either.
Dealer did his best.
Tern support and their supply network. Very Poor.

As for the bike until then it was a great round town commuter bike.

By the way I live in Dublin Ireland.

Hope nobody else has experienced this failure. Could have been quite serious if it had collapsed in heavy city traffic.

Ed
EdEllis is offline   Reply With Quote
Old 03-21-17, 09:57 AM   #2
shrooms
Senior Member
 
Join Date: Apr 2015
Location: Brooklyn NY
Bikes: Two Cannondale Hooligan 8s
Posts: 207
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 44 Post(s)
Next time you make some research before you buy another bike. We have many threads about Tern frame failures.
shrooms is offline   Reply With Quote
Old 03-21-17, 10:25 AM   #3
ThorUSA
Senior Member
 
ThorUSA's Avatar
 
Join Date: Dec 2013
Location: Olney Illinois USA
Bikes: to many
Posts: 965
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Have you contacted Mark Bickerton in the UK ? He is the Tern guy over there, and would have helped immediately.
Please let me know who you contacted at Tern. I will forward it to the Owner and make sure that emails like yours will be handled swiftly and without any fuss ...
My experience is very limited with these bolts breaking, I had one instance where the frame latch was not adjusted correctly ( way way to loose ) which put undue stress on those bolts, we could however unsrew the broken part and replace with new pins and bushings





Did you get your money back ? Or a new frame ?
let me know
Thanks Thor
ThorUSA is offline   Reply With Quote
Old 03-21-17, 11:21 AM   #4
Bonzo Banana
Senior Member
 
Join Date: Feb 2017
Bikes:
Posts: 172
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 58 Post(s)
I never understand the appeal of Tern and Dahon bikes, forums are full of frame failure issues, there has been recalls and a recent post I saw about a Dahon bike showed the tolerance between the seat post and frame was poor causing frequent movement of the saddle in use. Do not represent the expected quality for their price point.

Also it seems they are just buying frames of their design from other manufacturers, they create a lot of their own patents and design but actual production quality seems unremarkable to say the least. I realise it may be that these are performance bikes and perhaps some of the issues are in the pursuit of lightness but as many cycle for health a few extra pounds here and there isn't the end of the world. I'd rather cycle a heavy bike I can depend on than something I'm unsure about. The issue with Dahon is different because the max.com bikes made in Bulgaria may be different quality to the Chinese made bikes, I don't know who is better at making Dahons. Dahon just seems like one of those bike brands that invest heavily in marketing and are set at a premium price point but you wonder if they really warrant these prices. Certainly the frames don't look any better made than budget bikes.

Not trying to offend any Dahon or Tern fans but I don't think these brands represents the sweet spot between quality and value. I honestly think some of the one step up models of direct sellers of folding bikes who import directly from the Chinese factories and sell direct to the public offer the best value. The bikes that have good quality aluminium frames, gearing above tourney quality and a cassette based rear wheel not freewheel. Just my opinion. I have no vested interest in saying that and have no connection with such direct sellers and understand if you have no ability to service a bike yourself then buying from a local bike shop at a higher price is recommended for all the additional support they can offer.
Bonzo Banana is offline   Reply With Quote
Old 03-21-17, 12:17 PM   #5
ThorUSA
Senior Member
 
ThorUSA's Avatar
 
Join Date: Dec 2013
Location: Olney Illinois USA
Bikes: to many
Posts: 965
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Dahon makes the frames themselves
https://www.facebook.com/Thorusa-977019502329957/


just saying.
thor
ThorUSA is offline   Reply With Quote
Old 03-23-17, 03:12 AM   #6
Bonzo Banana
Senior Member
 
Join Date: Feb 2017
Bikes:
Posts: 172
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 58 Post(s)
Quote:
Originally Posted by ThorUSA View Post
Dahon makes the frames themselves
https://www.facebook.com/Thorusa-977019502329957/


just saying.
thor
Well someone needs to rewrite the Dahon wikipedia page then and tell max.com bikes in Bulgaria about it. Even on the wiki page it says assembly plants which is normally a description of facilities that merely assemble parts from elsewhere. What Dahon wants to state to the public and what actually happens are two different things. Would Dahon state we buy in frames to our design from another chinese manufacturer, reducing their weight and strength and then assemble the bikes in our factories and sell them at a premium price well beyond similar folding bikes?

Also their facebook comment is clearly rubbish. 100% manufactured means everything which is clearly false with all the third party components and they state a single factory where as the european bikes at least some of them are coming out of Bulgaria and a Macau plant is mentioned on the wikipedia page. I mean how much more false can that statement get?

Also on that video the frame welding looks to be manual which would be an indication of steel frames because aluminium is difficult to weld by hand and is best done by robots. So it looks like they produce some steel bikes and likely buy in the aluminium frames. Most factories with welding robots are proud to show them. You can see its a fairly small factory with limited automation.

It reminds me of the Decathlon situation. I remember wondering how they designed a frame with a wierd geometry which looked so weak and likely to fail and the reality later on was it was horrifically weak and very dangerous. Decathlon had designed their frame and got it made in China which was nothing like the Chinese factories own designs and the frames were failing all the time and there has been a huge recall of about 4 years of production of the bikes. Sometimes its better not to be too creative and go with some old style over-engineering and proven designs.



Decathlon Recalls 2012-2016 E-Bikes - Bike Europe

Last edited by Bonzo Banana; 03-23-17 at 05:16 AM. Reason: update
Bonzo Banana is offline   Reply With Quote
Old 03-23-17, 05:24 AM   #7
Bonzo Banana
Senior Member
 
Join Date: Feb 2017
Bikes:
Posts: 172
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 58 Post(s)
Factory for comparison here;

Bonzo Banana is offline   Reply With Quote
Old 03-24-17, 10:46 AM   #8
ThorUSA
Senior Member
 
ThorUSA's Avatar
 
Join Date: Dec 2013
Location: Olney Illinois USA
Bikes: to many
Posts: 965
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Quote:
Originally Posted by EdEllis View Post
Hi. I purchased a Tern Link in December 2016. About 2 weeks ago the frame became wobbly. I noticed that one of the two frame hinge center bolts had sheared. Half of the bolt in the frame the other on the floor..
I took it back to the the dealers, who in turn called the suppliers. The suppliers Palegon in the UK wanted nothing to do with it. The dealer took it to a work shop and had the bolt drilled out, but in so doing stripped the thread.
Tern did not respond apparently.
I insisted on my money back. Nobody would offer any technical reason why the bolt failed, nor would they offer any guarantee that that the other bolt would not fail, nor that the repair wouldn't fail either.
Dealer did his best.
Tern support and their supply network. Very Poor.

As for the bike until then it was a great round town commuter bike.

By the way I live in Dublin Ireland.

Hope nobody else has experienced this failure. Could have been quite serious if it had collapsed in heavy city traffic.

Ed
Ed .... you will be contacted by a Tern representative shortly and you will get a new bike.
Give them a couple days as they are all on the Taiwan Trade show


Thor
ThorUSA is offline   Reply With Quote
Old 03-24-17, 11:52 AM   #9
Mark Bickerton
Junior Member
 
Join Date: Apr 2007
Bikes:
Posts: 10
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Hi Ed,

I am sorry you are having problems with service on your Tern Bicycle.

Your email to the Tern contact email address dated 21st March is already subject of an internal correspondence at Tern to try to find a way of resolving how to handle your case during the interim period between the old distributor (Paligap) and the new distributor (Moore Large), who has only just been appointed.

I am away in Taiwan for the Taipei show and wont be back in the office till Wednesday.
If we haven't already contacted you directly by then, please contact me by email.
(I don't normally monitor this forum, and have logged on because Thor and Tern HQ have brought this to my urgent attention.)

You can email me at "mark . bickerton @ Ternbicycles . com" (no spaces)

Best regards,

Mark Bickerton

P.S. I will email this response directly to you as well.
Mark Bickerton is offline   Reply With Quote
Old 03-25-17, 01:27 AM   #10
dahoneezz
Senior Member
 
Join Date: Aug 2016
Bikes:
Posts: 116
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 60 Post(s)
At least its not a frame failure. Maybe things are improving.
dahoneezz is offline   Reply With Quote
Old 03-25-17, 01:17 PM   #11
wesgreen
Senior Member
 
Join Date: Nov 2015
Bikes:
Posts: 61
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Quote:
Originally Posted by dahoneezz View Post
At least its not a frame failure. Maybe things are improving.
Thanks for that! Laughter is the best medicine!
wesgreen is offline   Reply With Quote
Old 03-25-17, 08:13 PM   #12
dahoneezz
Senior Member
 
Join Date: Aug 2016
Bikes:
Posts: 116
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 60 Post(s)
Quote:
Originally Posted by wesgreen View Post
thanks for that! Laughter is the best medicine!
dahoneezz is offline   Reply With Quote
Old 04-12-17, 09:03 AM   #13
EdEllis
Newbie
Thread Starter
 
Join Date: Mar 2017
Bikes:
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Tern Frame

Quote:
Originally Posted by dahoneezz View Post
Well Guys
I have had a long dialogue with Tern UK and Taiwan, they have been helpful. They provided the dealer with a new frame, with a different hinge mechanism. I like the bike so I will give it a try.
Unfortunately my old frame was black, they provided a white one, so now I am awaiting another new frame of the correct colour.

I will let ye all know how I get on

Ed
EdEllis is offline   Reply With Quote
Old 04-12-17, 10:03 AM   #14
ThorUSA
Senior Member
 
ThorUSA's Avatar
 
Join Date: Dec 2013
Location: Olney Illinois USA
Bikes: to many
Posts: 965
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
good. Thanks for coming back with at least a partial positive news. I am sure they will figure out the color for you.
Keep us in the loop will ya.


I hate to pad myself on the back. This should have been done by your dealer in the first place, instead of giving you the run around. Sometimes the manufacturer gets a bad rap cause a dealer doesn't do due diligence. Unfortunately happens way to often in the bike biz
Again sorry that it takes a little armtwisting ( actually not much, a simple email got things rolling in a hurry )
but glad that you get a new frame
Thor
ThorUSA is offline   Reply With Quote
Old 04-12-17, 10:37 AM   #15
tdonline
Senior Member
 
Join Date: Jul 2016
Bikes:
Posts: 209
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 113 Post(s)
Thor, good job. If I was Ed, I would be side-eyeing his dealer...

Edit: to be fair, I don't know what level of effort his dealer made. Maybe he/she did make an effort and didn't get far with Tern. Ed did mention that Tern hadn't responded. Then it goes public on a forum and Tern steps up.
tdonline is offline   Reply With Quote
Old 04-15-17, 02:23 AM   #16
BromptonINrio
Junior Member
 
Join Date: Apr 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Wow, great work from thor to make and mantain contact bridges with tern. We all worried the these frame failure stories.
BromptonINrio is offline   Reply With Quote
Old 04-18-17, 10:38 AM   #17
Mark Bickerton
Junior Member
 
Join Date: Apr 2007
Bikes:
Posts: 10
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Hi All,
Just for the record, as soon as this was brought to Tern Global's attention, I was alerted and stepped in. Normally a retailer would get support from his supplying distributor, but as I explained we are still setting all the new systems up with our new distributor for UK and Ireland, so somewhere the service failed for Ed.

Having said that, any contact to Tern through email, the Tern website, twitter or facebook gets responded to by the team as a matter of priority.... so I would say that whilst a post on here may have had the desired effect for Ed, it isn't following the standard operating procedure for a customer service request!

Anyway, between Tern Global and the UK team we are hopefully getting Ed sorted....even if we got the frame colour wrong the first time.... ugh.

Mark Bickerton At tern bicycles . com
Mark Bickerton is offline   Reply With Quote
Old 04-20-17, 07:57 PM   #18
sweeks
Senior Member
 
sweeks's Avatar
 
Join Date: Sep 2004
Location: Chicago area
Bikes: Airborne "Carpe Diem", Trek 6000, Strida 2, Dahon "Helios XL", Dahon "Mu XL", Tern "Verge S11i"
Posts: 454
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 206 Post(s)
Comments on Comments ^^

I've been on this Forum for several years, but haven't checked in for a long time. I have a Tern Verge S11i which I bought almost four years ago (from Thor, as a matter of fact!). I've got 4,700 miles on it, accumulated by daily riding to and from work.
My frame was recalled last year. It was not cracked, and I was tempted to keep riding it because I felt able to catch the problem before it got to the breaking point. Tern was very persuasive and I submitted to a frame replacement. The new frame design has significant improvements to strengthen the frame joint area. I feel confident that the frame crack era is in the past.
As for the pivot bolts breaking (the "little brother" of the frame cracks), the new frame design uses a single hinge pin which is *much* less likely to be a problem.
There were some growing pains in Tern's first few years, but these issues have been sorted, IMO. The bikes are not inexpensive, but anyone who thinks they are poorly-made junk is sadly misinformed.

(Hi, Thor and Mark!)
Steve Weeks
Attachments: View of underside of frame showing weld for internal gusset plate; View through frame vent hole showing gusset plate; The VS11i with the new frame
Attached Images
File Type: jpg Tern Verge S11i Frame weld IMG_1383.jpg (91.0 KB, 288 views)
File Type: jpg Tern Verge S11i Frame Hinge Forward Frame Gusset IMG_1398.jpg (92.0 KB, 289 views)
File Type: jpg Tern VS11i new frame.jpg (97.0 KB, 286 views)
sweeks is online now   Reply With Quote
Old 04-20-17, 08:18 PM   #19
Abu Mahendra
Senior Member
 
Join Date: Jan 2016
Location: Bali
Bikes: Dahon Dash P18, Dahon Dash Altena, Bannard Sunny.
Posts: 1,181
Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 386 Post(s)
The damage has been done, and most of it was self-inflicted.

I've also had less than stellar communications with Tern Singapore about a Kinetix Pro X wheelset recently.

Not impressed. Tern has competitors.

Quote:
Originally Posted by sweeks View Post
I've been on this Forum for several years, but haven't checked in for a long time. I have a Tern Verge S11i which I bought almost four years ago (from Thor, as a matter of fact!). I've got 4,700 miles on it, accumulated by daily riding to and from work.
My frame was recalled last year. It was not cracked, and I was tempted to keep riding it because I felt able to catch the problem before it got to the breaking point. Tern was very persuasive and I submitted to a frame replacement. The new frame design has significant improvements to strengthen the frame joint area. I feel confident that the frame crack era is in the past.
As for the pivot bolts breaking (the "little brother" of the frame cracks), the new frame design uses a single hinge pin which is *much* less likely to be a problem.
There were some growing pains in Tern's first few years, but these issues have been sorted, IMO. The bikes are not inexpensive, but anyone who thinks they are poorly-made junk is sadly misinformed.

(Hi, Thor and Mark!)
Steve Weeks
Attachments: View of underside of frame showing weld for internal gusset plate; View through frame vent hole showing gusset plate; The VS11i with the new frame
Abu Mahendra is offline   Reply With Quote
Old 04-20-17, 08:39 PM   #20
sweeks
Senior Member
 
sweeks's Avatar
 
Join Date: Sep 2004
Location: Chicago area
Bikes: Airborne "Carpe Diem", Trek 6000, Strida 2, Dahon "Helios XL", Dahon "Mu XL", Tern "Verge S11i"
Posts: 454
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 206 Post(s)
You're certainly entitled to your opinion. Other manufacturers have had their rough patches as well. From my perspective, things are looking up for Tern, and I enjoy my daily ride. :-)
Steve
sweeks is online now   Reply With Quote
Old 04-20-17, 09:55 PM   #21
jur
Senior Member
 
Join Date: May 2005
Location: Melbourne
Bikes:
Posts: 7,274
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 228 Post(s)
Thanks for posting the frame improvements Steve. It's been something I and others have been wondering about, whether Tern have made specific weld improvements. That gusset is almost exactly something I suggested on this forum for a very cheap, easy weld strength improvement.
jur is online now   Reply With Quote
Old 04-20-17, 10:20 PM   #22
dahoneezz
Senior Member
 
Join Date: Aug 2016
Bikes:
Posts: 116
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 60 Post(s)
Quote:
Originally Posted by sweeks View Post
I've been on this Forum for several years, ... [snip]...

(Hi, Thor and Mark!)
Steve Weeks
Attachments: View of underside of frame showing weld for internal gusset plate; View through frame vent hole showing gusset plate; The VS11i with the new frame
From the pics, it looks like they run a weld bead along the frame. You mean there is a plate which is slotted through the front tube? No gusset at the back end of the hinge (hinge portion towards rear of bike)?
dahoneezz is offline   Reply With Quote
Old 04-20-17, 10:36 PM   #23
tmesis
Member
 
Join Date: Aug 2014
Bikes:
Posts: 35
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Quote:
Originally Posted by sweeks View Post
There were some growing pains in Tern's first few years, but these issues have been sorted, IMO. The bikes are not inexpensive, but anyone who thinks they are poorly-made junk is sadly misinformed.
The OP bought his problematic Tern bike in December 2016. That's less than six months ago.
tmesis is offline   Reply With Quote
Old 04-20-17, 11:16 PM   #24
jur
Senior Member
 
Join Date: May 2005
Location: Melbourne
Bikes:
Posts: 7,274
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 228 Post(s)
Quote:
Originally Posted by dahoneezz View Post
From the pics, it looks like they run a weld bead along the frame. You mean there is a plate which is slotted through the front tube? No gusset at the back end of the hinge (hinge portion towards rear of bike)?
I am guessing from what I see in the pics, that a gusset is welded as a butt weld against the hinge face plate, after which the front tube is welded to the hinge face plate. The gusset is flush with a slot in the main tube. A weld is run around the gap between the gusset and the frame slot.

What I suggested at the time was a fin protrusion into a gap in the main tube, with the weld tracking around that protrusion, greatly strengthening the weld joint. This is basically exactly what was implemented, only the fin is a separate piece welded onto the hinge plate instead of being in one piece (which would have been much better albeit more expensive). Effectively, the butt weld has been lengthened. My original suggestion would have been far stronger due to a shear weld being much stronger than a butt weld.
jur is online now   Reply With Quote
Old 04-21-17, 04:59 AM   #25
sweeks
Senior Member
 
sweeks's Avatar
 
Join Date: Sep 2004
Location: Chicago area
Bikes: Airborne "Carpe Diem", Trek 6000, Strida 2, Dahon "Helios XL", Dahon "Mu XL", Tern "Verge S11i"
Posts: 454
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 206 Post(s)
Quote:
Originally Posted by dahoneezz View Post
From the pics, it looks like they run a weld bead along the frame. You mean there is a plate which is slotted through the front tube? No gusset at the back end of the hinge (hinge portion towards rear of bike)?
That's right. All the reported frame failures were at the front of the frame joint.
Steve
sweeks is online now   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 07:01 PM.


 
  • Ask a Question
    get answers from real people!
Click to start entering your question.
I HAVE A QUESTION