I've fitted a kill switch to the underside to my seat that once on completely disables my motor via the kill switch ,I also pull the choke up full so there's no chance my motor can be started in a flash ,and yes it has been proven to work , some of the members here had a crazy but good idea of a CDI bypass directly to the bike frame so if someone tries to steal it they get a boot ,great idea but I suppose as the saying goes prevention is better than a cure.
I use a heavy duty motorbike cable that can only be cut with an angle grinder so for someone to steal it they would have to be meddling with the cruiser for a fair bit of time giving me the chance to catch them .
You can also get bike alarms that come with a key ring , once activated they make a very loud siren if vibration is detected and also alert you to possible threat with a key ring that has a receivable distance of a few hundred feet as well some models come with an online tracking ability ,the downside to these units is they can be smashed and rendered useless but hopefully one would be able to return to their bike before this could occur.
The issue I have is idiots sitting on my bike or knocking my bike over ,I've had it happen several times where I've locked her up and stood her up so she can't fall ,gone into the shop ,come out and she is on her side or some idiot is sitting on her and doing the typical throttle twist with accompanying motorbike noises sigh
I usually start with can I help you ,some are apologetic but others get a tad abusive and start with what's your problem ( usually the drunks) that's where I come back with get off my bike or I'll swing my helmet up side of your head ,they are usually very compliant
Regards Henshooter