Are lock alarms prone to going off accidentally?

[Cyclopathic]

Having only seen an advert for a couple of such things which both said that they were motion sensitve I wonder what the likelyhood is that they can be set off by the next person who locks their bike next to mine in the rack. Obviously I won't always be within earshot so I just imagine the thing blaring away until I return or the battery runs out. It seems likely they have a timer but even so it will be bloody irritating to anyone who is near it.

So what are the pros and cons of lock alarms?

I am going to run an experiment using an ordinary motion alarm of the sort used to stick to a door or a window to detect a blow. They have an on/off switch and variable sensitivity and I was thinking of just plastic tieing one undr the saddle or hidden by the rack.
I will report back my findings but I am hoping that no scroats try to "help" with my trials by nicking my bike.

 

[Davidc]

I've used alarms for a long time.

Both bikes have bolt-on motion sensing alarms which don't give much trouble*.

I also have alarm padlocks which I use with a cable to try to protect front wheel and panniers when in dodgy areas. Those are very good, but difficult to lock or unlock without them going off.

Both of these devices have a time out - they are after all battery operated so couldn't sustain a long sounding time. There are occasional false alarms, usually when the wind is blowing. They do go off when other people put their bikes on the same stand.

The definition of success is blood left as the toe-rags move fast to get away - twice in the past few years.


* Except when Muddyfox and Chuffy of this forum get too close at a tea stop.

 

[e-rider]

it should stop after 20 minutes otherwise it's breaking the law!