12 Dec 2018: Safety issue – carbon rims & pads

12 Dec 2018: Safety issue – carbon rims & pads

12 Dec 2018: Safety issue - carbon rims & pads


I have been made aware of a safety issue which can arise from the
need for very specific brake blocks to be used on some brands of
carbon rims. If the user manual is lost and non-approved aftermarket
pads (even those advertised as "for carbon rims") are used, there is
a safety problem.

This issue can be addressed at very low cost and I have made
recommendations below for precautionary actions by manufacturers,
distributors and retailers.

These recommendations are for durable labelling of the rims, and for
appropriate wording on packaging and online descriptions for pads
sold as "for carbon rims" but which are not in fact compatible with
specific brands of carbon rim.


A cyclist bought a set of used carbon-rim wheels (but without the
user manual). They then bought a set of brake pads described as "for
carbon rims". These turned out to be dangerously incompatible with
those particular carbon rims, and an accident occurred.

There are two issues here:

(a) The buyer of used carbon rims/wheels not being aware of the need
to use specific pads

(b) The buyer of pads marketed as "for carbon rims" understanding
this to mean "for all carbon rims" when in fact they were dangerous
when used with his particular carbon rims.

Braking safety concerns must always be taken seriously, even though
this may not seem a very common scenario. Thankfully both issues can
be addressed at very low cost.

No measures will completely prevent the possibility of end users
using incompatible pads, but the recommendations below should much
reduce the risk of this particular type of accident recurring.


(1) Carbon rim/wheel manufacturers

If your rims require specific brake pads, check that this is clearly
stated on a durable label attached to the rim (many brands already do
this). This means it will be obvious even if the user manual is
missing that only specific pads can be used.

Also, review the information you have online and ensure that
customers can quickly and easily find details of which specific pads
are compatible with your rims (for both current and previous product

(2) Brake pad retailers

Review the online product descriptions and retail packaging for all
brake pads marketed as "for carbon rims". Ensure that there is a
warning visible to end users before purchase to the effect of e.g.

"Check your rim or wheel user manual to confirm compatibility before

or more briefly e.g.

"Confirm rim compatibility before use"

(3) Distributors (pads and rims)

If either labels (on rims) or warnings (on pads packaging and
descriptions) are not in place as above on relevant products which
you distribute, request from your suppliers that they are put in
place at the earliest opportunity.

If you provide product descriptions for P&A to retailers
electronically/automatically (for them to use in online shops etc.)
ensure that appropriate warnings are included in carbon rim brake pad
descriptions, as above.


I know that many BA members are already keenly aware of the issues
around carbon rim/pad compatibility and have put appropriate measures
in place. However, unless you're certain you're not affected, please
do review the aspects listed above.

If you have any questions, or insights to pass on, please do contact
me at any time.

With best regards,


Peter Eland
Technical Manager
Bicycle Association of Great Britain




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