• Sale
  • ¥500
  • Regular price ¥17,100

*Two anti-theft bolts and a special tool can be selected as options. (Sold as a set with the device only.)
*Two standard bolts for installation are included.
*A separate service fee will be charged.
*If you use PayPal payment, the currency conversion will occur on the PayPal side. Please note that the price may fluctuate depending on the exchange rate.

Free for the first 30 days

Customer Reviews

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20% discount now! | Free shipping | 30-day return policy


Prevents theft and tampering.

Bike: De Rosa Protos and others

After my Pinarello Dogma was stolen, I started using AlterLock to prevent theft and tampering. Awareness is the key to prevention. I’ve installed AlterLock on all my bikes.

I was so relieved my bike was saved!

Luka Pyon
Bike: Merida Reacto 8000-E

I saw someone checking out my road bike, but I was too far away to do anything. He pulled a tool out of his pocket and broke the lock. However, AlterLock detected the vibration and sounded the alarm, scaring him off.

It's great to have security and peace of mind.

Bike: Specialized Venge Pro

I bought AlterLock after hearing the buzz about it. I used to have a standard wire lock and was worried about leaving my bike while shopping at the convenience store. With AlterLock’s excellent security, I now have peace of mind. It’s rock-solid dependable—no doubt about it!

All three road bike concerns are covered!


  • Worried if even the most robust locks will be enough to protect it?


  • Worried about leaving your bike unattended—even for a short time?


  • Afraid to take your eyes off your bike for even a moment?

Why AlterLock?


Alarms & Notifications


Smartphone notifications


Monitor via Bluetooth


GPS & WiFi Tracking


Fine Controls


Small, Lightweight, and Inconspicuous

App Features

  • ・Register your bike's photo, specs, and VIN number
  • ・Toggle the device lock mode
  • ・Device settings (for various situations including vibration detection level, alarm on/off, alarm duration, first alarm sound, number of alarms, regular transmission, etc.)
  • ・Push notifications and audible alarms when the device detects vibration or receives location information
  • ・View location and history while tracking on the map screen
  • ・Tracks maintenance history for safer riding
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Easy Installation


Install the app


Subscribe to Cycle Guard Service


Register your bike and device in the app


Attach the device

Device Specifications

Size 159mm long x 38mm wide x 9mm thick
Weight 50g
Battery Lithium polymer
Charging terminals USB Type-C
charging cable not included
Temperature Operating Temperature -20~60℃⁣⁣⁣⁣⁣⁣
Chargeable Temperature 0~45℃
Uptime Up to 1.5 months⁣⁣⁣⁣ (varies according to usage)
Communications Bluetooth Low Energy / Sigfox
Location Tracking GPS (GNSS) / Wi-Fi
Water/Dustproof IP66
Accessories Start guide, 2 mounting bolts
Options 2 anti-theft bolts, special tools
*Only sold in sets with the device


Product Price €134.99/£114.99(tax included)
Service Fee £3.49/month,£34.99/year(tax included)
€3.99/month,€39.99/year(tax included)

Communication Areas

AlterLock transmits data via Sigfox (the LPWA communication standard) when outside of Bluetooth range. LPWA makes it possible for the device to communicate on its own with low power consumption and low cost. Since Sigfox has different communication bands in different regions, Alterlock comes in several editions.

The European version is available in the following countries: Belgium, Croatia, Czech Republic, Denmark, France, Germany, Hungary, Ireland, Italy, Luxembourg, Portugal, Slovakia, Spain, Netherlands, United Kingdom and Finland.


Can AlterLock be installed on any bike?

It can be attached to a standard sports bike using its bottle holder's base or in conjunction with your existing bottle holder.

What areas can I use this service in?

It can be used within Sigfox's service area (primarily Europe). Outside the service area, all functions will work within the Bluetooth transmission range. You can check the service area from this page.* Even within the service area, notifications may not reach your smartphone indoors where the signal is weak or in an environment with poor reception.

How is AlterLock different from Bluetooth trackers?

Bluetooth trackers are challenging to track once they leave your hands. AlterLock has stand-alone communication and GPS, so you can track your device wherever you go.

Can I check my location anytime?

This product is designed specifically for theft prevention. It cannot be used as a GPS tracker that continuously displays location information. Vibrations made in lock mode activate the GPS to significantly reduce power consumption and enable long-term tracking.

Can the device be removed easily?

If you try to remove the device, AlterLock detects the vibration and sounds an alarm to notify you, so you can rush to your bike. If you're still concerned, an additional anti-theft bolt and special tool are available. Please consider purchasing the device as a set. These items are not sold separately.

Is it possible to adjust the volume of the alarm and the sensitivity of movement detection?

Yes, it is. The movement detection sensitivity can be set to one of three levels.

Proudly engineered in Japan