After many attempts with low cost carriers I've picked out the Thule carriers: First Price Check: Amazon was by far the cheapest provider. For carrier: Mounted without screws on the roof (crossbar). Lockable. The bike can have a very thick frame; the carrier can be set in two areas. Fixation with a lockable lid and two garter belts for the wheels. In summary: For me, an almost ideal carrier. And I do not get percentages from Thule.