I
bought this 18 inch battery cable to be used with the helmet lock. This
worked well enough but it was very stiff and hard to fit through the
helmet and a jacket sleeve.
Something less bulky and more flexible was needed, but it had to be
something that would not rattle or damage the side panel.
(Yeah - I know that back rest bracket has to be sanded and repainted;
as soon as summer heat returns!)
Browsing the WWW, I found a firm making security cables for computers. High strength tempered steel, and plastic coated.
This (1/8 inch by 24 inches) coiled cable was only a few dollars delivered to my door.
It might be cut with a bolt-cutter, but not by a knife, not even a BIG knife!
The cable can be had with your choice of terminations -- these are swaged loops at $1.00 each
As you see, the loops fit easily in the Helix's helmet holder space.
A much longer cable of this type could easily be used here without being noticeably obtrusive.
The cable came from "The Tufnut Works" -- --
(http://www.tufnut.com)
located in Tesuque, New Mexico. Check them out!