Jockeys (6)
I believe the answer is:
riders
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">jockeys</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for riders that I've seen before include "they mount up" , "Jockeys" , "Travellers on bikes or horses" , "Clauses appended to a legislative bill" , "Clauses appended to legislative bills" .)