AlterLock bike alarm

An unobtrusive bike alarm and tracker that works via a smartphone app

(Image credit: Future)
Cycling Weekly Verdict

AlterLock is a neat, unobtrusive way to add an alarm to your bike and to track if it does go missing. It’s easy to use and gives an extra measure of comfort that your bike will be where you left it. But the longer distance comms to your smartphone requires a subscription and has patchy coverage in much of the UK.

Reasons to buy
  • +

    Compact, light bike alarm that won’t ruin your bike’s aesthetics

  • +

    Lots of options to parameterise

  • +

    Tracking if your bike does go missing

Reasons to avoid
  • -

    Wireless comms coverage is patchy in hilly areas

  • -

    Alarm is probably not noisy enough to deter the determined thief

  • -

    On-going subscription required

You can trust Cycling Weekly. Our team of experts put in hard miles testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.

Leaving your bike when you’re out for a ride is always a bit of a nerve-racking experience. Unless you carry your best bike lock (and a supplementary cable lock), which rather spoil a recreational ride, you’re never quite sure if your bike is safe, even if you’re only leaving it for a few minutes to queue for a coffee.

Even carrying a small cable lock around feels like a misuse of valuable pocket space, and it’s not going to deter any but the most opportunist of thieves. 

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Paul Norman

Paul started writing for Cycling Weekly in 2015, covering cycling tech, new bikes and product testing. Since then, he’s reviewed hundreds of bikes and thousands of other pieces of cycling equipment for the magazine and the Cycling Weekly website.

He’s been cycling for a lot longer than that though and his travels by bike have taken him all around Europe and to California. He’s been riding gravel since before gravel bikes existed too, riding a cyclocross bike through the Chilterns and along the South Downs.