The Yorkshire motive may be seen as disloyalty (7)
I believe the answer is:
treason
'disloyalty' is the definition.
(treason is a kind of disloyalty)
'the yorkshire motive' is the wordplay.
'the yorkshire' becomes 't' (I've seen this in other clues).
'motive' becomes 'reason' (reason is a kind of motive).
't'+'reason'='TREASON'
'may be seen as' acts as a link.
(Other definitions for treason that I've seen before include "Lese-majesty" , "rebellion" , "Serious crime" , "LEse-majestE" , "Crime of disloyalty" .)