Bike locks with alarms pair a physical barrier with a sound alert, but they vary in what they can secure and how much protection they offer when an alarm is ignored. My best overall pick is the BLACKSTONE Stainless Steel U Bike Lock, which combines a U-lock format with a 130 dB alarm and a double-looped cable. The BANGTING 4Ft Heavy Duty Chain Lock stands out for locking around larger fixtures, while the Alarm U-Lock for E-Bikes is a more direct fit for riders who want an alarmed shackle-style lock. The main tradeoff is between a harder-to-cut physical lock, convenient alarm features, and the size or weight you’re willing to carry. Read on for how all 12 options compare and which type fits your bike and parking routine.
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Key Takeaways
- The BLACKSTONE U-lock pairs a stated 130 dB alarm with a double-looped cable, giving it a broader setup than disc locks, which are made for compatible brake rotors.
- The BANGTING chain’s 4-foot length is a practical advantage when the rack or fixed object sits farther from the bike; a longer reach does not, by itself, mean stronger security.
- Alarm volume is only one part of deterrence. The lineup’s stated levels range from 110 dB to 130 dB, but lock placement, sensitivity, battery readiness, and how quickly an alarm can be silenced also matter.
- Disc locks are specialized, not general-purpose bike locks. The YOHOOLYO, 110 dB alarm disc lock, URBAN UR6, and rechargeable 120 dB disc lock suit compatible motorcycles better than bikes that need a frame-to-rack connection.
- Remote controls, rechargeable power, and extra cables add convenience, not a guarantee of stronger protection. Check the locking format, materials, weather rating, and everyday carrying needs before choosing those extras.
| bike locks with alarm | Alarm volume | Weight | Lock type |
|---|---|---|---|
| YOHOOLYO Alarm Disc Lock Motor | 110 dB | 12.32 oz | — |
| Alarm U-Lock for E-Bikes | — | 3.2 lb | — |
| BANGTING 4Ft Heavy Duty Bike C | 110 dB | — | — |
| Mengshen Bike Lock with Remote | 115 dB | — | Digital cable lock |
| Anti-Theft Bike Alarm Chain Lo | 110 dB, adjustable | — | — |
| Alarm Disc Lock | 110 dB | 0.39 kg | Alarm disc lock |
| URBAN UR6 Hi-Tech Motorcycle D | 120 dB | — | Motorcycle disc lock with alarm |
| Rechargeable Motorcycle Disc L | 120 dB | — | Motorcycle disc lock with alarm |
| Bike U Lock with 113dB Alarm S | 113 dB | 1.2 kg | Alarm U-lock |
| Bike Chain Lock with Alarm | 110 dB | 3.42 lb | Alarm chain lock |
| Heavy Duty Anti Theft Alarm U | — | 3.2 lbs | — |
| BLACKSTONE Stainless Steel U B | 130dB | — | — |
More Details on Our Top Picks
YOHOOLYO Alarm Disc Lock Motorcycle Disc Brake Lock Anti-Theft Waterproof 110 dB 7mm Pin with Reminder Cable and Carry Pouch
The YOHOOLYO keeps its alarm close to the wheel: its 110 dB siren sounds when the disc lock is disturbed, while the 7 mm pin can be positioned around the brake disc. Its waterproof design, reminder cable, and carry pouch make it a practical package for riders who want a small secondary deterrent rather than a chain to carry. Compared with the BANGTING 4Ft Heavy Duty Bike Chain Lock, it is much easier to stow but cannot secure a wheel to a fixed object. The included cable helps remind you to remove the lock before riding; it does not add meaningful anchoring strength. The tradeoffs are its reliance on replaceable batteries and the possibility of false alarms in windy conditions. I’d choose it for compactness, not as a substitute for a primary lock.
Pros:- 110 dB alarm adds an audible warning when the disc lock is disturbed.
- Waterproof, rust-resistant design suits outdoor parking.
- Includes a 5-foot reminder cable, carry pouch, two keys, and Allen wrench.
- 360-degree pin positioning gives flexibility when fitting the lock to a brake disc.
Cons:- A disc lock alone cannot anchor the bike to a rack or other fixed object.
- Alarm batteries require replacement over time.
- Wind or incidental movement may trigger false alarms.
Best for: Motorcycle, scooter, and compatible bicycle owners who want a compact alarmed disc lock with a reminder cable for short stops.
Not ideal for: Riders who need to lock a frame or wheel to a rack, or who want a chain-style lock that can anchor the vehicle to a fixed object.
- Alarm volume:110 dB
- Pin diameter:7 mm
- Weather protection:Waterproof
- Pin adjustment:360-degree positioning
- Included accessories:Two keys, Allen wrench, 5-foot reminder cable, carry pouch
- Weight:12.32 oz
- Warranty:Lifetime
Our verdict“Choose the YOHOOLYO for portable, alarmed wheel security on compatible disc brakes, but pair it with an anchor-capable lock when the bike must be secured to an object.”
Alarm U-Lock for E-Bikes, 5/8″ Hardened Steel, Motion Alarm, Red
This alarmed U-lock is the lineup’s sturdier, more structured option for owners whose fat-tire e-bike needs to be secured through its frame and a fixed object. The 5/8-inch hardened-steel shackle and motion alarm combine physical resistance with an audible deterrent, while the rubber coating helps prevent contact marks on the frame. Its opening measures 5 by 6 inches, so fit is a real buying constraint: check the rack, frame, and tire clearance before choosing it. Compared with the YOHOOLYO disc lock, this can anchor a bike rather than just immobilize a wheel, but it is far bulkier at 3.2 pounds. Weatherproof construction and three laser-cut keys suit regular outdoor use; the cost of that coverage is carrying weight and less flexibility than a chain.
Pros:- 5/8-inch hardened-steel shackle adds substantial physical structure.
- Motion-sensor alarm provides an audible warning against tampering.
- Rubber-coated shackle helps protect bike paint from scratches.
- Weatherproof construction and three laser-cut keys support routine outdoor use.
Cons:- At 3.2 pounds, it is a heavy everyday carry.
- The fixed shackle opening requires careful fit checks and offers less placement flexibility than a chain.
- The product data does not specify alarm volume or battery details.
Best for: Fat-tire e-bike and scooter owners who can verify the shackle opening fits their frame and parking rack and want an alarm built into a hardened-steel U-lock.
Not ideal for: Commuters who prioritize a light, easily packed lock or whose frame-and-rack setup exceeds the 5-by-6-inch shackle opening.
- Shackle material:Hardened steel
- Shackle thickness:5/8 inch
- Shackle opening:5 inches wide × 6 inches tall
- Overall dimensions:7 inches wide × 9 inches tall
- Weight:3.2 lb
- Alarm:Built-in motion-sensor alarm
- Weather protection:Weatherproof
- Keys:Three laser-cut keys
Our verdict“Pick this U-lock for a compatible fat-tire e-bike that needs alarmed frame-to-rack security, and skip it if carrying weight or uncertain fit is a concern.”
BANGTING 4Ft Heavy Duty Bike Chain Lock with 110dB Alarm, Waterproof Security Lock for Bicycle, Electric Bike, Scooter, Motorcycle, Gate, Fence (Black)
The BANGTING combines a 4-foot chain with a 110 dB alarm, making it the most adaptable choice here for reaching around larger frames, racks, gates, or fences. Its manganese-steel construction is intended to resist cutting and sawing, while the IP65 rating supports use in wet outdoor conditions. Unlike the Alarm U-Lock for E-Bikes, the chain can wrap around awkward parking points, but that flexibility comes with more bulk to carry and less rigid geometry. Remote controls add convenient operation, though the lock also needs USB-C charging—a maintenance step the battery-powered YOHOOLYO disc lock avoids. The loud alarm can attract attention, but its volume may be unwelcome in quiet shared spaces. I’d favor this model when reach and anchoring options matter more than packability.
Pros:- Four-foot chain offers flexible reach around frames and fixed objects.
- Manganese-steel construction is designed to resist cutting and sawing.
- 110 dB alarm adds a clear audible deterrent.
- IP65 water protection and included remote controls support outdoor use and convenient operation.
Cons:- Heavy chain construction makes it less convenient to carry than a disc lock.
- USB-C charging adds a recurring upkeep task.
- The alarm may be excessively loud for some shared or quiet parking areas.
Best for: E-bike, bicycle, and scooter owners who regularly need to secure a vehicle to varied or oversized fixed objects and can carry a heavier chain.
Not ideal for: Light-travel commuters or riders who want to avoid charging an alarm lock or need a compact lock for quick stops.
- Chain length:4 ft
- Materials:Manganese steel and zinc alloy
- Alarm volume:110 dB
- Charging connection:USB-C
- Included accessories:Keys, remote controls, silicone cover, carrying bag, USB-C cable
Our verdict“Choose the BANGTING when flexible, alarmed anchoring is more valuable than low carry weight or minimal maintenance.”
Mengshen Bike Lock with Remote Control Anti-Theft Vibration Alarm IP55
The Mengshen stands apart from the chain and disc-lock options with a remote-operated cable lock and password unlocking. Its 31-inch, 10 mm coated steel cable is easier to route through a bike and nearby fixture than the rigid U-lock, and the remote can operate from up to 40 meters away. A stated 115 dB alarm is louder than the 110 dB alarms on the BANGTING chain and YOHOOLYO disc lock, but volume is only one part of security: a flexible cable does not offer the same rigid barrier as a hardened-steel U-lock or chain. IP55 protection helps with outdoor exposure, while three AAA batteries mean replacements are part of ownership. This suits riders who value remote operation and flexible routing; I would not make it my sole choice where resistance to cutting is the main concern.
Pros:- Remote control offers locking and unlocking from up to 40 meters away.
- Password unlocking provides an alternative access method.
- 115 dB alarm sounds when vibration or tampering is detected.
- IP55 protection and coated cable support outdoor use.
Cons:- Flexible 10 mm cable is less rigid than the BANGTING chain or hardened-steel U-lock.
- 31-inch length limits reach compared with a 4-foot chain.
- Three AAA batteries need replacement, and remote sharing is limited to eight remotes.
Best for: Riders who want remote locking and unlocking, a flexible short cable, and an alarm for everyday stops near their bike.
Not ideal for: Owners seeking a heavy-duty primary barrier against cutting or a longer reach for securing a bike around distant fixtures.
- Lock type:Digital cable lock
- Cable length:31 inches
- Cable diameter:10 mm
- Cable material:Steel with plastic coating
- Alarm volume:115 dB
- Weather protection:IP55
- Battery:Three AAA batteries
- Remote range and capacity:40 meters; up to 8 remotes
- Operating temperature:-10°C to 60°C
Our verdict“Choose the Mengshen for remote convenience and flexible short-range locking, not as the lineup’s strongest choice against cutting.”
Anti-Theft Bike Alarm Chain Lock 8mm x 4ft with Remote Control and Key – Heavy Duty Steel, Rechargeable, Waterproof
This 4-foot chain offers an appealing middle ground for riders who want flexible anchoring without relying on disposable batteries: its 8 mm hardened-steel chain pairs with a rechargeable 110 dB alarm, remote control, and adjustable alarm volume and sensitivity. The stated standby time of up to 60 days reduces how often charging may be needed, though it still requires attention before the battery runs down. Compared with the BANGTING 4Ft Heavy Duty Bike Chain Lock, it shares the same chain length and alarm rating but adds stated volume and sensitivity adjustments plus a specific standby claim. Both remain heavier and less compact than the YOHOOLYO disc lock. A four-foot chain also takes up space in a bag, and sensitivity adjustments do not remove the possibility of false triggers in windy conditions.
Pros:- Four-foot chain can reach around a frame and fixed object.
- Hardened-steel chain measures 8 mm in diameter.
- Rechargeable alarm includes a stated standby time of up to 60 days.
- Adjustable alarm volume and sensitivity allow some tailoring to the parking environment.
Cons:- Chain length and construction make it cumbersome to carry.
- The alarm needs charging for continued operation.
- Wind or movement may still cause false triggers despite adjustable sensitivity.
Best for: Bike and e-bike owners who need a four-foot anchor-capable chain, prefer rechargeable power, and want control over alarm sensitivity and volume.
Not ideal for: Riders who want a very compact lock, do not want to monitor charging, or mainly need an alarmed disc lock for brief stops.
- Chain length:4 ft
- Chain diameter:8 mm
- Material:Hardened steel
- Alarm volume:110 dB, adjustable
- Alarm sensitivity:Adjustable
- Power:Rechargeable
- Battery standby:Up to 60 days
- Water resistance:Waterproof
- Included accessories:Keys, remote controls, silicone cover, storage bag, USB-C charging cable
Our verdict“Pick this chain if you want flexible anchoring and adjustable, rechargeable alarm features, and accept the carrying bulk and charging routine.”
Alarm Disc Lock, 110 dB, 7mm Pin, with Reminder Cable and Carry Pouch
This disc lock suits riders who want an alarm plus a few practical extras in one package. Its 110 dB vibration alarm is less forceful on paper than the URBAN UR6’s 120 dB siren, but the included 5-foot reminder cable helps flag that the lock is fitted before you ride away. Heavy-duty steel and a waterproof design add weather protection, while the pouch makes it easier to carry the lock and spare batteries together. The tradeoff is its six LR44/AG13 batteries, which need monitoring and replacement, unlike the UR6’s long-life CR2 cell or the rechargeable alternative in the 120dB Rechargeable Motorcycle Disc Lock. Check your brake-disc dimensions: the pin is limited to compatible openings and discs up to 6 mm thick.
Pros:- 110 dB vibration- and shock-triggered alarm
- Waterproof heavy-duty steel construction
- Includes reminder cable, keys, batteries, and storage pouch
- One-press operation keeps arming simple
Cons:- Requires six LR44/AG13 button batteries that need replacement
- Fits only compatible disc brakes up to 6 mm thick
- Alarm may be excessively loud for some parking settings
Best for: Motorcycle or scooter riders who want a straightforward alarm disc lock with a reminder cable, pouch, and spare batteries included.
Not ideal for: Riders seeking low-maintenance power or a lock for disc brakes thicker than 6 mm; its six button batteries add upkeep, and fit is limited.
- Lock type:Alarm disc lock
- Material:Heavy-duty steel
- Alarm volume:110 dB
- Lock pin diameter:7 mm
- Battery:6 LR44 or AG13 button batteries
- Weight:0.39 kg
- Reminder cable:5 ft
- Applications:Motorcycles, bicycles, and scooters
Our verdict“Choose this if you want a bundled, easy-to-arm disc alarm and can accept battery upkeep and strict brake fit limits.”
URBAN UR6 Hi-Tech Motorcycle Disc Lock with Smart Alarm
The UR6 is the strongest fit here for riders who want a disc alarm without frequent battery attention. Its 120 dB alarm adds pre-alert beeps and an LED indicator, giving nearby people a warning before a full alarm sounds. Compared with the Alarm Disc Lock, 110 dB, 7mm Pin, this model uses a CR2 lithium battery rated for 2–3 years, rather than six button cells, and its replaceable electronic module can extend the lock’s useful life. Waterproof construction and a two-year warranty suit regular outdoor parking. The main compromise is fit: its 6 mm pin may not suit larger brake-disc holes. It also lacks the included reminder cable and pouch found with the other disc lock, and carrying it locked to the bike requires an optional mount.
Pros:- 120 dB alarm with LED indicator and pre-alert beeps
- Waterproof design for rain and humidity
- CR2 battery rated for 2–3 years of use
- Replaceable electronic module and two-year warranty
Cons:- 6 mm pin may not fit larger brake-disc holes
- Mounting brackets for carrying it on the bike are optional
- CR2 battery still needs replacement after its service life
Best for: Motorcycle commuters who park outdoors often and prefer a loud, weatherproof alarm with less frequent battery replacement.
Not ideal for: Riders whose brake discs have larger holes than the 6 mm pin fits, or anyone wanting an included carrying mount or reminder cable.
- Model:URBAN UR6
- Lock type:Motorcycle disc lock with alarm
- Pin size:6 mm
- Alarm volume:120 dB
- Battery:CR2 lithium; stated life 2–3 years
- Weather resistance:Waterproof
- Warranty:2 years
- Alarm features:LED indicator and pre-alert warning beeps
Our verdict“Pick the UR6 for a waterproof, loud disc alarm with fewer battery changes, provided its pin fits your brake disc.”
Rechargeable Motorcycle Disc Lock with 120dB Alarm
This model keeps the disc-lock format but replaces disposable cells with a 500 mAh rechargeable battery and Type-C charging. That makes it a useful alternative to the URBAN UR6 for riders who would rather recharge every few months than track a CR2 battery’s longer service interval. The 120 dB vibration alarm and IP67 rating suit bikes left outside, while the included 5-foot reminder cable and helmet lock add everyday utility. Its stated standby life is 2–3 months, so regular charging is part of ownership; riders seeking fewer power checks may prefer the UR6. Fit is also restricted to disc brakes no thicker than 7 mm, and the lock may feel bulky to carry. It offers more bundled accessories than the UR6, but not the same long battery interval.
Pros:- 120 dB vibration-triggered alarm
- Rechargeable 500 mAh battery with Type-C charging
- IP67 weather-resistance rating
- Includes a 5-foot reminder cable and helmet lock
Cons:- Stated standby life of 2–3 months means recurring charging
- Only compatible with disc brakes up to 7 mm thick
- Bulk may make it less convenient to carry
Best for: Motorcycle, scooter, or bicycle owners with compatible disc brakes who prefer USB-C recharging and want a reminder cable and helmet lock included.
Not ideal for: Riders who want to avoid charging every few months, need a compact lock, or have disc brakes thicker than 7 mm.
- Lock type:Motorcycle disc lock with alarm
- Alarm volume:120 dB
- Vibration sensor:Yes
- Battery:500 mAh rechargeable
- Charging port:Type-C
- Battery life:2–3 months standby
- Weather resistance:IP67
- Brake compatibility:Disc brakes up to 7 mm thick
- Included cable:5 ft reminder cable
Our verdict“Choose this rechargeable disc lock if you want a loud alarm and useful cable accessories, and are comfortable charging it every few months.”
Bike U Lock with 113dB Alarm System, Heavy Duty Bicycle Lock with 4ft Security Cable & 17mm Shackle
Unlike the disc locks in this roundup, this U-lock can secure a frame to a fixed object, while its 4-foot cable adds reach for a second wheel or another component. The 17 mm carbide-steel shackle and 113 dB alarm make it the more versatile choice for a bicycle or e-bike parked at a rack; the URBAN UR6 and rechargeable disc lock depend on a compatible brake disc and do not provide the same frame-to-anchor setup. IP65 weather resistance supports outdoor use, and a mounting bracket helps with transport. That versatility comes at a cost in carry weight: at 1.2 kg, it is heavier than a small disc lock. The alarm uses three AAA batteries, so it also lacks the rechargeable convenience of the 8mm Bike Chain Lock.
Pros:- 17 mm carbide-steel shackle for frame-to-anchor locking
- 113 dB alarm adds a motion deterrent
- 4-foot cable extends locking options
- IP65 weather resistance and included mounting bracket
Cons:- 1.2 kg weight may be cumbersome for daily carrying
- Alarm requires three AAA batteries that need replacement
- Setup may take more effort for first-time users
Best for: E-bike and bicycle owners who need to lock a frame to a rack and want a cable for added reach or a second component.
Not ideal for: Riders prioritizing a light, compact carry or rechargeable power; this U-lock weighs 1.2 kg and its alarm relies on replaceable AAA batteries.
- Lock type:Alarm U-lock
- Alarm volume:113 dB
- Shackle diameter:17 mm
- Shackle material:Carbide steel
- Lock body material:Zinc alloy
- Cable length:4 ft
- Weather resistance:IP65
- Weight:1.2 kg
- Alarm batteries:3 AAA batteries
Our verdict“Choose this U-lock if frame-to-rack security and cable reach matter more than minimizing carry weight or avoiding disposable batteries.”
Bike Chain Lock with Alarm, 8mm Heavy Duty Security Lock for Bike, Scooter, Motorcycle
For riders who need more placement flexibility than a disc lock allows, this chain gives a 4-foot reach and an 8 mm alloy-steel chain, with a 110 dB vibration alarm controlled by remote. Compared with the Bike U Lock with 113dB Alarm System, it trades a rigid shackle and mounting bracket for a chain that can wrap around different frames and anchors. Its USB-C rechargeable battery is rated for up to 60 days of standby, avoiding the U-lock’s AAA replacements, though it still needs routine charging. At 3.42 lb, it is a substantial load for a daily ride, and its 110 dB alarm is quieter on paper than the U-lock’s 113 dB and the disc locks’ 120 dB options. The included keys, two remotes, cover, and bag make the package practical, but not lightweight.
Pros:- 4-foot chain offers flexible frame-to-anchor placement
- 110 dB vibration alarm with remote control
- USB-C rechargeable battery with up to 60 days of standby
- Includes three keys, two remotes, silicone cover, and storage bag
Cons:- 3.42 lb weight is burdensome for some daily riders
- Requires charging to keep the alarm powered
- 110 dB alarm is less loud on paper than the 120 dB disc-lock options
Best for: Bike, scooter, and motorcycle owners who need a flexible chain to reach a fixed anchor and value remote operation and USB-C charging.
Not ideal for: Commuters who want a light everyday carry or a longer interval between power checks; the chain weighs 3.42 lb and standby is stated at up to 60 days.
- Lock type:Alarm chain lock
- Material:Alloy steel
- Chain diameter:8 mm
- Chain length:4 ft
- Weight:3.42 lb
- Alarm volume:110 dB
- Control method:Remote
- Battery:USB-C rechargeable; up to 60 days standby
- Included components:Lock, 3 keys, 2 remotes, silicone cover, storage bag, and USB-C cable
Our verdict“Pick this chain if flexible anchoring and remote-controlled, rechargeable alarm operation matter more than keeping your carry load light.”
Heavy Duty Anti Theft Alarm U Lock for E-Bikes, Scooters, Motorcycles – 16mm Stainless Steel, 3 Keys, Weatherproof
This lock suits riders who want an alarm-equipped U-lock for regular outdoor parking, with a 16mm stainless-steel shackle and a weatherproof, rubber-coated finish. The coating helps protect the frame from scratches, while the motion sensor adds a warning layer if someone tampers with the lock. Compared with the BLACKSTONE U-lock, this model has a thicker stated shackle and a taller 6-inch opening, but its alarm volume is not specified, so buyers have less information about how far the alert may carry. Its three included keys are useful for keeping a spare, and the stated warranty and US-based support add reassurance. The tradeoff is practical: at 3.2 pounds, it may feel cumbersome to carry, and its 5-by-6-inch opening will not suit every frame or fixed locking point.
Pros:- 16mm stainless-steel shackle offers a substantial physical barrier.
- Weatherproof construction is suited to outdoor parking.
- Rubber-coated shackle helps prevent scratches to the bike frame.
- Includes three keys, giving the owner spare access options.
Cons:- At 3.2 pounds, it adds noticeable weight to a daily carry.
- The 5-by-6-inch shackle opening may not fit all frames or locking points.
- Alarm volume is not specified, making alert audibility harder to judge.
Best for: E-bike and scooter owners who park outdoors and want a weatherproof alarmed U-lock, a scratch-resistant coating, and spare keys.
Not ideal for: Commuters who prioritize low carry weight, or riders whose frame and parking points need a wider or taller shackle opening.
- Shackle diameter:16mm
- Material:Stainless steel
- Weight:3.2 lbs
- Shackle opening:5 inches wide × 6 inches tall
- Overall dimensions:7 inches wide × 9 inches tall
- Weather protection:Weatherproof design
- Included keys:3
- Color options:Black or red
Our verdict“Choose this for a weatherproof, thick-shackle alarm U-lock if its opening fits your bike and you can tolerate the extra carry weight.”
BLACKSTONE Stainless Steel U Bike Lock with 130dB Alarm and Double-Looped Steel Cable
The BLACKSTONE is the more flexible choice here for riders who need to secure more than the frame: its 52-inch double-looped cable can help attach a wheel or accessory alongside the bike, while the U-lock anchors the main frame. Its specified 130dB alarm also gives buyers a clearer idea of the alert level than the Heavy Duty Anti Theft Alarm U Lock, whose volume is unstated. The tradeoff is a 14mm shackle, thinner than that model’s 16mm shackle, so riders focused on shackle thickness may prefer the other pick. This lock uses 304 stainless steel and includes three keys, but the cable adds bulk, and the supplied CR2 battery will eventually need replacement. It makes the most sense when cable reach and a stated alarm rating matter more than keeping the setup compact.
Pros:- Specified 130dB alarm makes its alert level clear to buyers.
- 52-inch double-looped cable adds reach for securing a wheel or accessory.
- 304 stainless-steel construction is rust-resistant.
- Includes three keys and a CR2 lithium battery.
Cons:- Its 14mm shackle is thinner than the 16mm shackle on the Heavy Duty Anti Theft Alarm U Lock.
- The cable and U-lock make for a bulky setup compared with a standalone lock.
- The CR2 lithium battery will need replacement over time.
Best for: E-bike and scooter owners who want one alarmed U-lock plus a long cable to secure a wheel or accessory as well as the frame.
Not ideal for: Riders seeking the thickest shackle in this pair or a compact, light setup for frequent carrying.
- Material:304 stainless steel
- Shackle diameter:14mm
- Alarm volume:130dB
- Cable length:52 inches
- Cable thickness:12mm
- Dimensions:13 × 8 × 3 inches
- Battery included:1 CR2 lithium battery
- Included keys:3
- Warranty:12 months
Our verdict“Pick the BLACKSTONE if cable reach and a clearly stated 130dB alarm matter more to you than a thicker shackle or a compact carry.”
How We Picked
I compared the 12 options by the job their alarmed lock can actually do: connect a bicycle to a fixed object, secure a wheel or frame, or immobilize a compatible motorcycle. I looked at the stated lock format, material and shackle or chain dimensions where supplied, alarm specifications, weather-related claims, and included accessories such as cables, remotes, keys, and reminder cords. Those details matter because a loud alarm cannot make up for a lock that does not fit the bike or the parking point.
The ranking gives priority to versatility, physical locking utility, and a clear alarm-and-lock combination, then accounts for convenience and specialized use. That favors general-purpose U-locks and chains over rotor-only disc locks for most bicycle owners. I treat advertised sound levels and security claims as specifications, not proof that every alarm will perform the same way in real parking conditions; limited detail about alarm adjustment, battery life, and independent security testing also counts against a product.
| bike locks with alarm | Lock type |
|---|---|
| YOHOOLYO Alarm Disc Lock Motor | — |
| Alarm U-Lock for E-Bikes | — |
| BANGTING 4Ft Heavy Duty Bike C | — |
| Mengshen Bike Lock with Remote | Digital cable lock |
| Anti-Theft Bike Alarm Chain Lo | — |
| Alarm Disc Lock | Alarm disc lock |
| URBAN UR6 Hi-Tech Motorcycle D | Motorcycle disc lock with alarm |
| Rechargeable Motorcycle Disc L | Motorcycle disc lock with alarm |
| Bike U Lock with 113dB Alarm S | Alarm U-lock |
| Bike Chain Lock with Alarm | Alarm chain lock |
| Heavy Duty Anti Theft Alarm U | — |
| BLACKSTONE Stainless Steel U B | — |
Factors to Consider When Choosing Bike Locks With Alarm
Choosing among bike locks with alarms starts with the lock’s physical job, not the loudest number on the package. Use these points to match the style to your bike, parking place, and willingness to carry extra weight.
Choose a Lock That Can Secure the Bike to Something Fixed
A lock can prevent a wheel from turning and still leave the whole bicycle easy to carry away. For street parking, check that the lock can pass through the frame and around a fixed rack or post; a chain or U-lock often serves this purpose better than a rotor-only disc lock. Measure the spaces you commonly use, since a small shackle may be secure but too short for bulky racks. Avoid relying on a cable as the only barrier unless its construction is specifically suited to your risk level. A disc lock can make sense as an extra layer on a compatible motorcycle, but it is not a substitute for anchoring the frame. Match the lock’s shape to your actual parking routine before weighing alarm features.
Read Alarm Claims as One Layer of Deterrence
Decibel figures can help compare advertised alarm output, but they do not tell you how easily the sound carries through traffic, walls, or a busy bike room. Alarm behavior matters too: check whether the unit reacts to vibration, movement, or tampering, and whether sensitivity can be adjusted. A setting that triggers at every bump may lead you to switch the alarm off; one that is too insensitive may give little warning. Ask how the alarm is armed and silenced, especially if you will lock and unlock the bike several times a day. Do not assume a remote, a high decibel figure, or a motion sensor makes the physical lock harder to defeat. Treat the sound as a chance to attract attention, not a replacement for a strong lock and good parking.
Balance Lock Strength Against Carrying Weight and Reach
Thicker steel and longer chains can offer practical benefits, but they can also make a lock less pleasant to carry on every ride. A chain’s reach helps when the parking fixture is awkwardly placed; it does not automatically mean its links or locking mechanism resist attacks better. A compact U-lock may be easier to transport, yet its internal opening can limit what you can secure. Compare dimensions against the frame, wheel, and rack combinations you actually use. If the lock stays in a home garage or pannier, weight may matter less than if you carry it on your back. Choose the lightest format that still gives you the reach and physical coverage your parking spots require.
Check Power, Weather, and Maintenance Details
Alarm locks depend on working electronics, so a dead battery can remove the feature that separates them from a conventional lock. Rechargeable models call for a charging routine; battery-powered versions still need occasional checks and replacement cells. Look for specific weather information rather than assuming that words like waterproof mean the lock will tolerate every season or storage condition. Rain, road grit, and long periods outdoors can affect both the mechanism and electronic components. Keep keys or a backup access method separate from the bike, and learn how to silence or reset the alarm before relying on it away from home. A simple maintenance habit is more useful than buying extra features you may not keep powered.
Match the Lock Type to the Vehicle
Disc locks are designed for brake rotors and only fit when the pin, rotor opening, and brake setup are compatible. That makes them compact and useful for some motorcycles, but a poor main choice for a bicycle that needs to be attached to a rack. U-locks and chains are more adaptable for anchoring a frame, though their size and carrying demands differ. Check the product’s stated vehicle use rather than assuming that a listing mentioning bicycles, scooters, and motorcycles means one lock works equally well for all of them. E-bikes may justify a heavier lock because of their value and weight, while also making portability more challenging. Base the choice on where the lock engages and what it physically secures.
Pay for Useful Details, Not Feature Count
Remote control, a reminder cable, a second cable, or a rechargeable alarm can make a lock easier to use, but each feature should solve a problem you actually face. A reminder cord can help prevent riding away with a disc lock attached; a remote may be convenient when the alarm is mounted out of reach. Neither accessory tells you how resistant the main lock is to cutting or forced entry. Before paying for add-ons, check for clear dimensions, material information, alarm operation details, and a practical way to carry the lock. When those basics are unclear, a simpler model with a suitable locking format may be the safer choice. Prioritize a lock you will use correctly on every stop over one with a long feature list.
Frequently Asked Questions
Can an alarmed disc lock protect my bicycle at a rack?
Usually, a disc lock is meant to attach to a compatible brake rotor, not to secure a bicycle frame to a fixed rack. It can discourage a bike from being rolled away, but the entire bike may still be lifted or carried. For public bicycle parking, choose a lock that can pass through the frame and connect it to a fixed object. A disc lock may work as an added layer on a compatible motorcycle, especially when its rotor and pin dimensions match. Check fit before buying, and do not treat it as a substitute for an anchor lock.
Is a 130 dB alarm meaningfully better than a 110 dB alarm?
A higher stated figure suggests a louder advertised alarm, but it does not alone tell you how useful the alert will be in your parking environment. Distance, surrounding noise, alarm placement, and the unit’s trigger behavior all affect whether anyone notices it. A loud alarm on a lock that cannot secure the frame properly is still a poor match for rack parking. Compare the physical lock and how the alarm is armed alongside the decibel claim. Favor a setup you can maintain and use consistently over choosing by the largest number alone.
Should I choose a chain or an alarmed U-lock for an e-bike?
Choose based on the racks you use and how much lock you are willing to carry. A chain can reach around larger fixtures and awkward frame shapes, while a U-lock may be easier to position and carry but limited by its opening. Compare link or shackle specifications and the lock’s overall dimensions rather than assuming the style alone decides strength. E-bikes can be heavy and valuable, so securing the frame to a fixed object matters more than merely immobilizing a wheel. If the bike is often parked in different places, favor the format that reliably fits those locations.
Do remote controls or rechargeable batteries make an alarm lock more secure?
They can improve convenience, but they do not necessarily strengthen the physical barrier. A remote may make arming and silencing easier, while a rechargeable alarm needs a charging routine to keep that feature available. Check what happens when the battery runs down and how the lock can be opened or reset without the alarm. Also confirm that the main lock still secures the bike effectively if the electronics fail. Treat power and control features as usability details, not evidence of resistance to cutting or forced entry.
Can one alarmed lock work for both my bicycle and my motorcycle?
Sometimes, but shared product listings do not guarantee a practical fit for both vehicles. A chain or U-lock may be adaptable if its dimensions suit each frame and the fixed objects you use. A disc lock requires compatible brake hardware, so fit can differ between vehicles and it will not anchor either one to a rack by itself. Compare the lock’s physical opening, chain length, pin size, and stated use against both vehicles before relying on one purchase. If either vehicle is regularly parked in a public place, prioritize a lock that can secure it to a fixed object.
Conclusion
For most riders seeking one alarmed lock for everyday bicycle parking, my best overall choice is the BLACKSTONE Stainless Steel U Bike Lock, thanks to its U-lock format, stated 130 dB alarm, and included double-looped cable. The best value in practical coverage is the BANGTING 4Ft Heavy Duty Chain Lock for riders who need extra reach, while the best premium-style pick is the URBAN UR6 for motorcycle owners seeking a dedicated smart-alarm disc lock. For beginners, the Alarm U-Lock for E-Bikes offers a straightforward shackle format; check its fit against your frame and parking rack before buying. For specific motorcycle use, compare the YOHOOLYO and other 7 mm-pin disc locks with your rotor, and choose a chain or U-lock instead if you need to anchor a bicycle. The right choice is the one that physically fits your vehicle and parking spot, with an alarm you can keep powered and use reliably.
