How much do you hate keys? That is the question at the heart of TMD’s new chain lock, a Bluetooth-enabled keyless lock that promises to eliminate the need for physical keys when securing your bike. Priced at $280, it is far more expensive than a traditional high-quality chain lock, which can be had for around $60. The lock is aimed at the growing demographic of e-bike owners and city cyclists who lock and unlock their bikes multiple times a day.
What Makes the TMD Chain Lock Different?
TMD, a company that previously focused on securing ATMs for banks, applies its keyless expertise to bicycles. The lock uses Bluetooth proximity detection to automatically unlock your bike when your phone is nearby. The core is made of hardened steel wrapped in a lightweight sleeve of Dyneema and Kevlar, making the lock both tough and flexible. It can be easily wrapped around a seat post while you ride.
Key Features and Performance
The TMD Chain Lock features a motion-activated 100dB alarm, ART-2 security certification (required by many European insurance companies), and the ability to share digital keys with friends and family. The lock is IP57 rated for water and dust resistance, and the battery is claimed to last up to nine months on a single charge. However, in real-world testing, the battery dropped 16% in a week, suggesting actual lifespan could be closer to six weeks if the lock is constantly within Bluetooth range of a phone.
Convenience is the main selling point. In daily use, the lock recognizes your approach and can be unlocked with a single button press – no fumbling for keys. But this comes with a trade-off. If your bike is parked within Bluetooth range (e.g., just outside a cafe window), anyone could potentially unlock it. TMD has not yet implemented a geofencing or time-based lock to prevent this. Also, if your phone is stolen, your bike key is gone too.
The Noise Problem
One of the most surprising drawbacks is the noise. The lock emits a loud 75dB tone each time it unlocks, drawing attention to you and your expensive e-bike. TMD has indicated a future software update will allow users to disable these sounds, but for now, it’s a significant annoyance. The alarm itself is less shrill than expected at 100dB, but it still does the job.
Charging and Connectivity
To maintain water and dust protection, TMD uses a proprietary magnetic charging cable instead of USB-C. This is a disappointment, as USB-C ports are now common on many phones and offer better IP68/69 protection. If the lock dies, you need that proprietary cable to recharge it. Recovery is quick: a dead lock springs back to life after two to three minutes of charging from a phone’s USB-C port.
Security and Insurance
The lock’s ART-2 certification means it meets the minimum standard required by many Dutch and European insurers for covering expensive e-bikes. Should your bike be stolen, the TMD app provides a digital log file as proof that your bike was locked, which can be sent to an insurance company. This is a valuable feature for owners of high-value e-bikes and cargo bikes.
Comparison with Traditional Locks
When compared to an equivalent analog lock, such as the ABUS 8900 chain lock (also ART-2 certified), the TMD lock costs roughly four times as much. For most cyclists, that price premium is not justified. The convenience of keyless operation is nice, but it comes with compromises like battery anxiety, noise, and the risk of Bluetooth proximity attacks. The lock is best suited for those who absolutely hate keys and need to share access digitally with multiple people, or for those who lock their bike frequently throughout the day in a controlled environment.
The Future of Keyless Bike Locks
TMD has plans to release an anti-angle grinder U-lock and a GPS-equipped ring lock later this year. If these locks can communicate with each other and unlock simultaneously via your phone, the convenience factor could increase significantly. But as a standalone product, the TMD Chain Lock is a niche solution for a small segment of cyclists. For the majority, a $60 traditional lock remains the smarter choice.
Source: The Verge News