Carbon downtube 'ding' 'squish' - repair advice please

Page may contain affiliate links. Please see terms for details.

Kernow_T

Über Member
Location
Cornwall
Hi
Looking to build this frame up but there's a small slight (see pics) that I want put right obviously. See pics for cleaning idea but it feels like the slightest ridge/fold (less than half a ml) along the crack lines. How should it be fixed and what might it cost - is there a 'make good' option?
Thanks in advance
 

Attachments

  • IMG_20180124_152453978.jpg
    IMG_20180124_152453978.jpg
    112.8 KB · Views: 132
  • IMG_20180124_152449079.jpg
    IMG_20180124_152449079.jpg
    140.8 KB · Views: 102

derrick

The Glue that binds us together.
That need a professional repair. looks like it's been quashed.
 

screenman

Legendary Member
Tightened without the use of a torque wrench, I have a frame with the same type of damage where the front mech sits.

Plenty of companies out there doing repairs or buy a diy kit.
 

Tangoup51

Well-Known Member
Is that the downtube or the seat tube? It looks like a seat tube, can't ever recall seeing a carbon downtube that small in diameter.

If it's the seat tube, chances are it's caused by the front derailleur being overtightened, or someone not tightening the seatpost clamp enough and the seat post slipped down into a pinch point of the tube and popped the tube open. Though you should have bottle cage rivets to prevent that.

If it's the downtube, chances are it was dropped on something or clamped by something.

There are multiple cracks in that area, I suspect that it was ridden after the crack formed and continued to stress the frame, either that or it took one hell of a knock altogether.


It's really important where abouts on that frame the crack is. If it's near a high-stress area, it's basically kaput. Anywhere that requires alot of tension or receives alot of force. Such as the headtube, bottom bracket, etc.

If it's in the middle of a tube, not so much. you can get DIY repair kits but you have to be competent. They are inexpensive but you really do need to know how to work with it.

Getting it repaired will cost you a big sum too. Probably more than it'd cost to buy a whole other carbon frame. Or 'least a second hand one that isn't cracked.


If you want my advice, I'd buy another frame, because even if you were willing to repair it yourself, after you build the bike up you'll be forever depending on your own last-minute DIY skills.
 
Last edited:
OP
OP
Kernow_T

Kernow_T

Über Member
Location
Cornwall
Down tube. Wonder what the don't use V (vert), H (hor) and D (diag) terminology
Here's a pic showing position
 

Attachments

  • IMG_20180124_194218141.jpg
    IMG_20180124_194218141.jpg
    105.6 KB · Views: 82

Tangoup51

Well-Known Member
Down tube. Wonder what the don't use V (vert), H (hor) and D (diag) terminology
Here's a pic showing position

That's a little too close to the bottom bracket to warrant a DIY repair.

Considering the position and severity of the crack(s) i'd say a carbon specialist will have a pretty long receipt for a price on that frame repair.

I can't give you a quote of price for sure, but anything between £200 and £350 should be expected. That doesn't include shipping costs either but the price can vary.
 
Last edited:
U

User10571

Guest
@User10571 had a carbon bike, down tube fixed.
Thanks to seeing what CF is actually capable of, during my tenure at The Science Museum, I'd probably carry on riding that and not give it a second thought.
As Ian says I have had a CF frame repaired, one that I'd inherited as a crash damaged item.
In the first picture, that hole just behind the gear cable is large enough to slot a £1 coin into it. It isn't a fissure or crack, it is a thru hole right into the down tube.
I've a friend who, at the time, was working for McLaren (Yes, the F1 outfit).
Thanks to him I had their CF lab look at the damaged frame and produce a report as to how to go about repairing it.
These guys:
http://carbonbikerepair.co.uk/?gclid=EAIaIQobChMIhN6SzsPx2AIVrbvtCh1ZDAJlEAAYASAAEgJgmfD_BwE
eventually got the gig, and effected a repair which went way beyond the spec which McLaren were recommending.
I wouldn't hesitate to recommend them.
I've been tearing around on the repaired bike for the last 2 or 3 years, putting a grin on my face, it has now been put back in the hands of the original owner.
If you decide to go the carbonbikerepair route, it is worth bearing in mind that the bulk of your money will go towards finishing (Prep, primer, paint, stickers, lacquer, etc), rather than the repair.
If you are able finish it yourself ( as I was) then you'll save a fortune.
G'luck
Interested to hear how you get on.

JB

8561461075_e16f03feec_b.jpg


8561460839_aa2e956841_b.jpg


8561460909_cabb244c1d_b.jpg


8562565512_426dc59eb9_b.jpg


8561460645_3df9879f29_b.jpg
 
Last edited by a moderator:
Top Bottom