Detection loops for bicycles

Andrew_B

Leaving to one side the discussion around the best type of detection for bicycles (best left for another discussion) and focusing only on loops

If specifying a detection loop for bicycles at a stop line, what shape and what orientation would you use and why. Particularly interested in views on Bow-Tie shape loops.

Also can anyone confirm success with detecting high end bicycles (carbon fibre frame and wheels) with loops. I'd imagine the only bit with a hope of being detected is the cranks/chain/pedals/gears and that a conventional loop doesn't stand a chance, and there seems to be more and more of that type of bicycle on the roads.

Thanks