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Product Warnings

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hellymedic:
I have copied this from the Audax thread but I feel this issue needs wider attention.

--- Quote ---This message was prepared by Ritchie Tout following an incident on the Bryan Chapman Memorial 600 k event May 2017.  If you're riding one, please check it out.  Note there is also a reference to a TREK headset at the end.  This was a separate incident.

"Advice re Specialized headshocks
 
I thought it was worth posting a note about an incident on last weekend’s BCM.  A rider discovered that her Specialized Ruby bike with a suspension system within the steerer meant that the steerer was not part of the fork.
 
The design is that the steerer slots into the fork crown and is held in place with a collar.  This collar is very thin and secured with a 4mm allen headed bolt.  All of this is hidden by a plastic cover with the allen bolt being accessed through the side of this.
 
It looks like it vibrated loose on the ride up to King’s but when she got there the bars no longer turned the fork. 
 
I have contacted Specialized but have not had a reply from them yet.  However, it is worth being aware of this problem as it is a system which is unique to Specialized and it is not obvious how it works – at least it wasn’t to us to start off with as nobody considered the possibility that the steerer column was not part of the fork.
 
I wonder whether AUK should keep a repository of incidents of this kind?  Had this rider crashed, I suspect anyone would have thought that the crash was what caused the loose steerer.
 
We also had a catastrophic failure of a Trek headset bearing.  The headset arrangement looked very flimsy in view of the forces transmitted through the headset bearings but it just splintered into several bits and left the bike unrideable."
 
 If you have one of these - do check it.  It may be a one - off or possibly more widespread, so collecting data is handy...

--- End quote ---

Cudzoziemiec:
A 4mm bolt seems incredibly small for such a stressed and important part.

T42:

--- Quote from: hellymedic on 18 May, 2017, 02:06:32 pm ---I have copied this from the Audax thread but I feel this issue needs wider attention.

--- Quote ---We also had a catastrophic failure of a Trek headset bearing.  The headset arrangement looked very flimsy in view of the forces transmitted through the headset bearings but it just splintered into several bits and left the bike unrideable."

--- End quote ---

--- End quote ---

It would be nice to know which Trek(s).  ???

aidan.f:
Cycle  manufacturers  are  always looking for some feature  to  encourage you to part with  more  cash. Often with unforeseen consequences. Don't  expect them to change anything as a  result of  your observations, after all that  would  be  an admission of  liability.

There was a case of bars with decorative machined grooves , of course  they broke. Several riders  were  seriously  injured.

It came to a court case brought by  the  good old  CTC when they employed Chris Juden C.Eng. to look after us. in Then the  new  look Cycling UK  made  him  redundant. So now  it is  a case of buyer beware.

robgul:

--- Quote from: Cudzoziemiec on 18 May, 2017, 02:20:09 pm ---A 4mm bolt seems incredibly small for such a stressed and important part.

--- End quote ---

4mm refers to the size of the hex wrench - that's pretty much the norm for all headset related bolts (the bolts could be oversize with a small head)   

As an example, some of the Scott bikes that we have in the shop have BIG bolts on the stem but are tightened with a 4mm hex wrench.

Rob

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