Strange you should ask. I'll be keen to see what ideas you come up with re vibration alarms. As one of my other passions is motorcycles, I'm are of a few disc locks with loud vibration alarms - of course, they don't HAVE to be mounted to a disc, so I'm scratching my head at the moment re options.
As far as locks go, the beauty of ebikes is that you can consider some very heavy locks that you might otherwise dismiss. I use the Kryptonite New York U-Lock through the seat stays & rear wheel, locked to something solid, coupled with an Abus covered steel rope thingy looped from the lock through front wheel & seat rails. The serendipitous bit for me is that the New York lock fits snugly into the bottom of my Carradice Super C Rack Pack without bouncing around. So snugly, in fact, that I have to put it in the right way round.
Everybody's situation is different .For me, I have a small ,very small cable and pad lock. It is for emergencies and very quick shopping, or maybe a quick walk to see the waterfall close up. I just won't leave my bike. I ride recreational only. Since bikes are light enough to be physically picked up I don't really trust any lock.
I have insurance to cover any loss but one of my main security concerns is returning to home or transport truck 40 miles away at 11pm with no cell signal on a mountain trail.
I use a Kryptonite U Lock with their strong steel cable as well, and my bike is always exactly where i left it. I commute and there's a growing number of really heavy chains with enormous locks permanently attached to a strong fence near work in the city which makes good sense as it's so much simpler just to carry the key.
I've got 2 kryptonite series 2 u locks (one is the pdx version, they are clearly the same just the pdx has slightly lower value replacement....doesn't matter since the bikes are insured), heavy cables to secure miscellaneous parts and also an abus iven lock which is my go-to these days, got a great deal on it last year at rei.
I like the abus because of the length, long enough to secure both mine and my wife's bike, along with 2 cables latched to the abus for front tires and seats.
I have an E-joe Epik SE on order so I am thinking about what I want to do to secure it.
Home: Bring it inside.
Work: The military base is very safe. I will probably leave a Kryptonite U Lock attached to the bike rack I go to.
Going to the store or out and about: This is where it is most likely to be stolen. I was thinking something like the Bully alarm lock. Seems like a good idea for a small store or restaurant where I could react, but maybe not so much for a large Mall. The lock itself doesn't look as secure as some of the other U locks, but the alarm is a great feature. Maybe I will get one of the other alarms that secures to the bike. Can't take the wheel off without setting off the alarm. Only thing is, if someone is willing to whip out an angle grinder and make all that noise, would an alarm really stop them?...
Anyone have a problem with people taking accessories like bike computers or lights or bags?
I tend to take all high-value accessories (including the Intuvia unit, the removal of which acts as an immobiliser to the electric power) with me.
My rack pack contains the lock & cable, which goes on the bike, my tools etc. in bags within a small drawstring bag, neoprene case for the Intuvia, sunglasses's case, & a large-ish drawstring kit-bag. When I park up, I can put all these things into the kit bag, along with helmet & gloves, & sling it over my shoulder. It's a handy habit to get into & I no longer find myself struggling with a helmet in shops etc. & banging it into things.
There are some 'interesting' high-tech products coming on to the market but some have obvious flaws (e.g. the smartphone-enabled lock that unlocks when you're in close proximity & alerts you to movement could have you inadvertently unlocking your bike as you rush to confront the potential thief):
For those looking for an alarm option, I've got a smarthalo on order that will sound an alarm if the bike is tampered with if you aren't in proximity of the bike.
I've also been thinking that something like the Bluetooth tile (first one you'll find in Anson searching there, it it's called the tile) would be an inexpensive stealth locator. In an urban area, if it is in proximity of anyone running the same app, you'll get notified of the tile location. In an urban area this might work well.
What I appreciated about @Carl_L 's post is the perspective that we're really trying to protect three different things: accessories (light, bags), components (seat, wheel) and the bike itself. So looking at the whole process as Carl did is a good reminder. It's not as simple as e.g. all the high-tech U-bolt products in the above video make it seem.
FWIW I think the main threats are locks which rely on a tumbler (youtube is full of keylock-defeat videos that make me shudder) and a $40 lithium-powered angle grinder with the right blade. When I would hacksaw off a frozen High-Test 3/8" chain shackle it would leave me winded and with a sore arm. The angle grinder made doing so a 10 sec job. You only have to walk around a boat yard for a spell to see how destructively effective one of those can be.
But here's a question I'd appreciate hearing comments on: One of my 'final four' is an iZip ProTour and it comes with what's commonly called a Cafe Lock. How easily defeated are these when compared against the typical (not expensive) cable lock or vinyl-covered chain & lock that also rely on a keyed tumbler? I realize their security doesn't compare with some of the ABUS and Kryptonite products, but I haven't even inspected a cafe lock up close yet and so would welcome some perspective on their effectiveness. Thanks!
The café lock only keeps someone from riding or pushing your bike away. It does not lock your bike to anything. So, easily defeated, someone can pick the bike up, put it in a vehicle and drive away all in a few seconds.
I had a Abus frame lock - aka cafe lock - installed on my (none ebike) Tout Terrain. It also has a chain option that plugs into the frame lock. Installation was done at the factory, I think. I really like it because it is quick and easy to lock up.
I also have Pit Locks on the front and rear wheels, the head tube, and seat post. I would not use a Frame Lock without a chain to wrap around something.