Main group of cyclists in a race (7)
I believe the answer is:
peloton
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">main group of cyclists in a race</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 peloton that I've seen before include "bunch of riders" , "Main body of riders in a cycle race" , "cyclists in bunch" , "Racing cyclists" , "Main packed group in a cycle race" .)