I first had the idea for something like this when I was a teenager so many years ago. I am now 70 years of age and yes bikes were being stolen directly off the rider even back then. My idea is based on the Dutch type Horseshoe lock but would be operated by panic push button and opened only with a key, the key being secreted on your person or, indeed not even carried if riding close to home and someone can bring you a the key. I know they aren't defeatable but would any mugger really want to hang around or carry a heavy ebike? I would have thought by now some big manufacturers would have produced something on that line. It has to be quickly operated and no key visible. At a pinch you could use the AXA type horseshoe lock and then fling the key but that takes time. It needs to be very quick if not instantaneous. Does anyone know of such a device or am I going to have to make one? I can more than likely modify the AXA Horseshoe.
I admire the thinking, but such a device needs IMHO, a remote control, just like most modern cars do today forlocking and unlocking.
What I fitted to my e-bike when it was new, was a rear light that fits under the saddle, is locked in position, and also contains an alarm that goes off if the bike is touched. Its quite loud and has a remote control.
Its also not that obvious either!
Recharging via a USB cable, and runs, if not using the light function, for 2 to 3 weeks.
Remote is good for 30 odd meters outside of any buildings, though I have not made any exact tests, and as it should be on when you leave the bike, that short range should not be a problem.
I carry a quality chain as well when shopping, and I use it!!
If you get hijacked,then you need to grab the remote in your pocket and activate the alarm without the thief seeing you do that!!
It costs less than 15 UK Pounds generally on ebay.
And will not damage any spokes either!!!
I hope this in some way helps you!
Regards
Andy