Uh oh. Cracking along the seat tube under the clamp...
#1
Senior Member
Thread Starter
Join Date: Feb 2011
Posts: 182
Bikes: 86 Nishiki Olympic Sport, 87 KHS Montana Team, 06 Dahon Mariner
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Likes: 0
Liked 5 Times
in
2 Posts
Uh oh. Cracking along the seat tube under the clamp...
All,
So, I noticed a small crack on the seat tube of my 2006 Dahon Mariner. The bike is more than 5 years old and therefore out of warranty.
Just after taking these photos, I've marked the length of the crack with a Sharpie, so that I can determine if the crack is growing. I have never ever ridden with the seatpost extended past its limit markings (in fact, I normally keep the seat post about half an inch lower than its limit), never hopped a curb, and I ride on a sprung Brooks Flyer (which I thought would absorb any excess stress.)
The following photos are taken with and without flash.
Any thoughts on a course of action? Repairs possible?
Thanks,
Warr
So, I noticed a small crack on the seat tube of my 2006 Dahon Mariner. The bike is more than 5 years old and therefore out of warranty.
Just after taking these photos, I've marked the length of the crack with a Sharpie, so that I can determine if the crack is growing. I have never ever ridden with the seatpost extended past its limit markings (in fact, I normally keep the seat post about half an inch lower than its limit), never hopped a curb, and I ride on a sprung Brooks Flyer (which I thought would absorb any excess stress.)
The following photos are taken with and without flash.
Any thoughts on a course of action? Repairs possible?
Thanks,
Warr
#2
Senior Member
Join Date: Jan 2009
Location: Bay Area, SF California
Posts: 1,513
Bikes: Dahon Speed TR and Dahon Speed Pro TT
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 5 Times
in
5 Posts
if you're the original owner, i know that there is a lifetime warranty on dahon frames. as long as you register it..or you could check with thor.
#3
Banned.
Join Date: May 2005
Location: Anti Social Media-Land
Posts: 3,078
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 3 Times
in
2 Posts
Just after taking these photos, I've marked the length of the crack with a Sharpie, so that I can determine if the crack is growing. I have never ever ridden with the seatpost extended past its limit markings (in fact, I normally keep the seat post about half an inch lower than its limit), never hopped a curb, and I ride on a sprung Brooks Flyer (which I thought would absorb any excess stress.)
Any thoughts on a course of action? Repairs possible?
Thanks,
Warr
Any thoughts on a course of action? Repairs possible?
Thanks,
Warr
- Repair it yourself (get quotes from reputable bike shops that are experienced with repairing cracked frame).
- Strip the bike of it's good parts and either sell those parts online as used-or keep the parts for future bikes to offset the financial loss as much as possible (my own choice of action for a previous bike).
- Buy another bike (the preferred option forced on most people for the flood of unrepairable or costly to repair bikes that cost more to repair than they are worth or even purchased new-like many to most imported-from-the-far-east products offered new nowadays, not just bikes).
Don't feel too bad. It is a real gamble for the longevity of most any selfsame products of any type by the comsumer.
I don't see how Thor could help here. I live only 15 miles away from Dahon's North America Headquarters. It is just a little office/warehouse combo with a few employees when I drove by on the way to visit my brother a few years back. Nothing impressive at all. I worked at the Sears Southern California Regional HQ and it was far bigger than that.
See for yourselves: https://maps.google.com/maps?q=833+Meridian+Street,+Duarte,+CA&hl=en&sll=37.0625,-95.677068&sspn=27.089481,44.736328&vpsrc=0&hnear=833+Meridian+St,+Duarte,+California+91010&t=h&z=16
Last edited by folder fanatic; 11-22-11 at 07:44 PM.
#4
Senior Member
Join Date: Aug 2005
Location: San Rafael, California
Posts: 2,097
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 113 Post(s)
Likes: 0
Liked 8 Times
in
6 Posts
Well, if this is the same 2006 Mariner you just bought on C/L for a song, then the frame is at least 4130 chromoly and weldable .... from the pictures (might be the angle) there seems to be quite a bit of 'pinching' at the top of the slot .. does it have a plastic or aluminum seat post sleeve? I'd pull the seatpost and sleeve out and see if the crack is all the way through to the inside ... you might be able fill and grind the crack early..
#5
Senior Member
Join Date: May 2005
Location: Albany, WA
Posts: 7,393
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 321 Post(s)
Likes: 0
Liked 7 Times
in
6 Posts
It might even be possible to use an aluminium seat post shim (assuming the one you have is plastic) and continue riding like that. Steveroot who used to be the kingpin on the Dahon forums has ridden with worse cracks no problem. AFAIK he rode one case where the crack was all the way through and around (so completely broken off) but he reinforced it with some sort of clamping arrangement and rode just fine.
Last edited by jur; 11-23-11 at 12:34 AM.
#6
New usename ThorUSA
Join Date: Nov 2004
Location: Southern Illinois USA
Posts: 2,469
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
lets see
thor
thor
#7
Senior Member
Thread Starter
Join Date: Feb 2011
Posts: 182
Bikes: 86 Nishiki Olympic Sport, 87 KHS Montana Team, 06 Dahon Mariner
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Likes: 0
Liked 5 Times
in
2 Posts
Um, I assume you meant to type more, Thor? ;-)
To answer other questions, I am not the original purchaser, it is made of 4130 ChroMo, and I do have the plastic sleeve around the seatpost. And it must be the angle of the photo - there's no pinching happening around the seat post clamp.
-Warr
To answer other questions, I am not the original purchaser, it is made of 4130 ChroMo, and I do have the plastic sleeve around the seatpost. And it must be the angle of the photo - there's no pinching happening around the seat post clamp.
-Warr
#8
Banned
As you saw the big slot has a round hole in the end,
you can drill a small hole at the end of that crack to stop it growing,
Until you can get the spot TIG re-welded, small bead, and a paint touch up..
I concur, if the shim is too small replacing it with one made to a tighter tolerance
will cause less flexing work the metal , a cause of that crack developing.
you can drill a small hole at the end of that crack to stop it growing,
Until you can get the spot TIG re-welded, small bead, and a paint touch up..
I concur, if the shim is too small replacing it with one made to a tighter tolerance
will cause less flexing work the metal , a cause of that crack developing.
#9
New usename ThorUSA
Join Date: Nov 2004
Location: Southern Illinois USA
Posts: 2,469
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Warr email me the frame number and I will see what I can do
also make a pic from the headset for me... there were two different sizes.
Dahon has a frame and we need to find out if that is the correct one ....
In any case I have a alloy shim which I personally like better than the plastic one... it might be all what it needs, but lets explore all possibilities first ...
thor
also make a pic from the headset for me... there were two different sizes.
Dahon has a frame and we need to find out if that is the correct one ....
In any case I have a alloy shim which I personally like better than the plastic one... it might be all what it needs, but lets explore all possibilities first ...
thor
#10
Senior Member
Thread Starter
Join Date: Feb 2011
Posts: 182
Bikes: 86 Nishiki Olympic Sport, 87 KHS Montana Team, 06 Dahon Mariner
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Likes: 0
Liked 5 Times
in
2 Posts
Warr email me the frame number and I will see what I can do
also make a pic from the headset for me... there were two different sizes.
Dahon has a frame and we need to find out if that is the correct one ....
In any case I have a alloy shim which I personally like better than the plastic one... it might be all what it needs, but lets explore all possibilities first ...
thor
also make a pic from the headset for me... there were two different sizes.
Dahon has a frame and we need to find out if that is the correct one ....
In any case I have a alloy shim which I personally like better than the plastic one... it might be all what it needs, but lets explore all possibilities first ...
thor
Message sent to what this forum thinks is your email addy. Lemme know if it's a no-show.
Have a great weekend.
-Warr
#11
Senior Member
Thread Starter
Join Date: Feb 2011
Posts: 182
Bikes: 86 Nishiki Olympic Sport, 87 KHS Montana Team, 06 Dahon Mariner
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Likes: 0
Liked 5 Times
in
2 Posts
Any other thoughts, anyone?
Thor, what's the price on an aluminum shim?
-Warr
Thor, what's the price on an aluminum shim?
-Warr
#12
New usename ThorUSA
Join Date: Nov 2004
Location: Southern Illinois USA
Posts: 2,469
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Thor
#13
Senior Member
Thread Starter
Join Date: Feb 2011
Posts: 182
Bikes: 86 Nishiki Olympic Sport, 87 KHS Montana Team, 06 Dahon Mariner
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 17 Post(s)
Likes: 0
Liked 5 Times
in
2 Posts
I sent an email to you about how to take the photo, exactly (I guess I didn't quite understand what you meant), but perhaps you didn't get it?
Can you PM me your email addy? Otherwise, shoot me your email address to me at:
and we can take this offline.
Thanks for your help.
-Warr (Warren Ernst)
(PS: email address posted as a pick in a feeble attempt to thwart spam.)
Thread
Thread Starter
Forum
Replies
Last Post
skiron_2500
Classic & Vintage
57
07-29-19 05:49 AM