As tomsdad says the rack and bash plate are indeed yamaha, same as mine purchased from yam dealer.

The three loops under the rack are designed to take and hold a u lock, pass the u lock under the rack from front to rear going through the loop that is on the right first then through the other two before refitting the lock mechanism and it will stay in place during transit. The front loop stops the lock sliding straight through and onto the floor.

Thats what my yamaha dealer informed me when I asked the same question as you.

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