Originally Posted by will_maxim
I had the same problem and bought this:
Kuryakyn License Plate Helmet Lock w/Mount - Universal
I have this lock. Be careful with the bolts. They are not long enough to reach all the way through the existing plate mount. Buy some longer bolts and don't try to modify the existing (experience talking). Other than that it works as advertized.
I had no trouble with the bolts, but I did have to buy some rubber washers to sandwich between the plate and the mounting bracket. My dealer had put in these thick rubber grommets with some non-standard license plate screws (reflectors on one side, wing nuts on the other). Once I got the washers in place with a little blue ThreadLocker, I was off and running with the provided nuts and bolts.
I have two relatively minor gripes with this lock. The first is that my plate is pretty low to the ground. I have to be careful about dropping the helmet when I lock it, because it can hit the ground. Second is having to carry a second key. My key ring is bulky as it is.
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