Fibre shown by service organisation for motorsport (6)
I believe the answer is:
raffia
'fibre' is the definition.
(I know that raffia is a type of fibre)
'service organisation for motorsport' is the wordplay.
I cannot quite see how this works, but
'service' could be 'raf' (Royal Air Force) and 'raf' is found within the answer.
This explanation may well be incorrect...
'shown by' acts as a link.
Can you help me to learn more?
(Other definitions for raffia that I've seen before include "Plant fibre used in weaving" , "Type of palm tree" , "Woven palm tree fibre" , "Palm used for weaving baskets, etc" , "Fibre from palm tree, used to make mats" .)