Author Topic: Broken titanium fork end  (Read 736 times)

Nelson Longflap

  • Riding a bike is meant to be easy ...
Broken titanium fork end
« on: August 23, 2017, 10:42:37 pm »
My son's 9 year old 2 speed Brompton with all the titanium bits was discovered to have a cracked fork end. The fork end seems to be created by using a press to squash and shape the fork blades rather than welding in a casting.

The odd thing is that when compared with a 2017 Brompton titanium fork end, the 2017 version is about twice as thick. Which makes me wonder if the reason for the increased thickness is a history of failures in the thinner titanium fork ends. What is the collective knowledge on the matter? Has anybody seem anything similar?

TIA
“Don’t buy upgrades, ride up grades."  (Eddy Merckx)

Re: Broken titanium fork end
« Reply #1 on: August 24, 2017, 05:18:58 pm »
Yikes, that sucks. I also have a ti/superlight. Can you give me some insight on hos this bike was used?
Rider weight, curb jumper?, cobblestone roads, etc. I'm trying to see if I can avoid the same fate. Any
possibility the factory will warranty?

My 6 speed titanium is from 2013; seems ok so far. Over 200 pounds, don't jump berms/curbs, ride in
pothole riddled streets. But I tend to avoid big holes.
https://www.youtube.com/watch?v=pNuuT-nRer4&index=37&list=UUHyRS8bRu6zPoymgKaIoDLA

LittleWheelsandBig

  • Whimsy Rider
Re: Broken titanium fork end
« Reply #2 on: August 24, 2017, 05:31:22 pm »
https://brompton.zendesk.com/hc/en-us/articles/115000554605
Apparently 5 years for frame parts.

I've not heard of a Brompton Ti fork failing in this manner before now.
Wheel meet again, don't know where, don't know when...

Nelson Longflap

  • Riding a bike is meant to be easy ...
Re: Broken titanium fork end
« Reply #3 on: October 19, 2017, 09:33:33 pm »
Thought I should draw this thread to a conclusion (with apologies for the delay - I've been busy on holiday) ... Brompton's customer service was excellent and provided a replacement titanium fork foc, despite the bike being out of warranty  :thumbsup:  The new fork ends are indeed thicker than the original ones.

One thing I learned talking to somebody who knows about metallurgy is that titanium, while inherently a strong material, is more brittle than steel. I wonder if this explains why some titanium parts crack due to minor flaws that steel would be able to tolerate?
“Don’t buy upgrades, ride up grades."  (Eddy Merckx)

Torslanda

  • Professional Gobshite
  • Just a tart for retro kit . . .
    • John's Bikes
Re: Broken titanium fork end
« Reply #4 on: October 19, 2017, 10:08:53 pm »
Cynical old me thinks the reason most Ti manufacturers offer a 'lifetime' warranty on a frame is because they know it's going to break.  Working on the assumption that around 5 - 10% of customers will keep the frame for ever, they keep their warranty returns at an acceptable level.
VELOMANCER

Well that's the more blunt way of putting it but as usual he's dead right.

Re: Broken titanium fork end
« Reply #5 on: October 22, 2017, 06:23:30 pm »
Did you get to keep the old fork?

Nelson Longflap

  • Riding a bike is meant to be easy ...
Re: Broken titanium fork end
« Reply #6 on: October 23, 2017, 07:26:23 pm »
Did you get to keep the old fork?
No.
“Don’t buy upgrades, ride up grades."  (Eddy Merckx)

quixoticgeek

  • Mostly Harmless
Re: Broken titanium fork end
« Reply #7 on: October 26, 2017, 09:11:12 am »

Not seen a crack at that end, but a friend here in .nl with a titanium fork had a big crack down the middle of the stearer tube.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Gattopardo

  • Lord of the sith
  • Overseaing the building of the death star
Re: Broken titanium fork end
« Reply #8 on: November 10, 2017, 10:21:53 pm »
Cynical old me thinks the reason most Ti manufacturers offer a 'lifetime' warranty on a frame is because they know it's going to break.  Working on the assumption that around 5 - 10% of customers will keep the frame for ever, they keep their warranty returns at an acceptable level.

Very hard to weld successfully.

Re: Broken titanium fork end
« Reply #9 on: November 13, 2017, 09:50:16 pm »

Not seen a crack at that end, but a friend here in .nl with a titanium fork had a big crack down the middle of the stearer tube.

J
That's far nastier. 
Never tell me the odds.