I have this on my S2R and I'm very happy with it
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Pager works great, it has a battery voltage reader and the adjustable perimeter sensor tells people to back off.
One wire to the battery and plug in the factory harness connector - easy, but for once read the instructions!
Pager battery works for weeks. If you have a weak bike battery, it will require a bike battery charger if you don't for several weeks.