Introduction
Thank you for choosing the YOHOOLYO Alarm Disc Lock. This device is designed to provide enhanced security for your motorcycle, bicycle, or scooter with its robust construction and integrated alarm system. This manual will guide you through the setup, operation, maintenance, and troubleshooting of your new disc lock.
What's in the Box
- 1 x Alarm Disc Lock
- 2 x Keys
- 1 x Allen Key (for battery replacement)
- 1 x 5ft Reminder Cable
- 1 x Carry Pouch
- 6 x LR44 Batteries (6 internal, 6 backup)

Image: All components included in the YOHOOLYO Alarm Disc Lock package, including the lock, keys, Allen key, reminder cable, carry pouch, and batteries.
Setup
- Unpack Components: Carefully remove all items from the packaging. Verify that all listed components are present.
- Initial Battery Check: The disc lock comes with pre-installed batteries. To ensure functionality, gently press the lock pin. A short beep indicates the alarm system is active.
- Familiarize with Keys: Two security keys are provided. Keep one in a safe place as a spare.
- Reminder Cable Attachment: Attach one end of the reminder cable to the disc lock and the other end to your vehicle's handlebar or brake lever. This prevents accidental riding with the lock engaged.

Image: An exploded diagram illustrating the internal components of the disc lock, including the anti-theft mechanism, 7mm lock core, and accessories like keys and the reminder cable.

Image: A detailed view of the disc lock alongside its two keys, emphasizing its robust and portable design.
Operating Instructions
Locking the Device
- Position the lock on your vehicle's disc brake rotor, ensuring the 7mm locking pin aligns with a hole in the rotor.
- Gently press down the lock cylinder until you hear a 'click' sound. This indicates the lock is engaged and the alarm system is armed. A single beep confirms the alarm is active.
- The alarm will activate if the lock detects significant movement or shock after a 5-second delay. It will emit a warning beep first, followed by the full 110 dB alarm if disturbance continues.

Image: A hand demonstrating the simple, keyless locking process by pressing down on the disc lock until it clicks into place.

Image: The disc lock visually representing its loud 110 dB alarm, designed to deter theft with its sensitive built-in sensor.
Unlocking the Device
Insert the key into the lock cylinder and turn it to disengage the lock. The alarm will temporarily deactivate upon unlocking.
Reminder Cable Usage
The 5ft reminder cable is an essential safety feature. Always connect it between the disc lock and your vehicle's handlebar or brake lever. This bright orange cable serves as a visual reminder to remove the lock before attempting to move your vehicle, preventing potential damage.

Image: A motorcycle secured with the disc lock on its front wheel, demonstrating the proper use of the orange reminder cable connected to the handlebar.

Image: A diagram illustrating the length and diameter of the reminder cable, showing its coiled and extended forms for clarity.
Product Application
The YOHOOLYO Alarm Disc Lock is ideal for a variety of vehicles with disc brakes, including motorcycles, bicycles, and scooters. Ensure your vehicle's disc brake has suitable holes or spokes for the 7mm locking pin.

Image: A collage showing the disc lock being used on a bicycle, scooter, and motorcycle, highlighting its versatility.
Video: An official demonstration of the YOHOOLYO Motorcycle Disc Lock Alarm Anti-theft in use, showcasing its features and how it secures a vehicle.
Maintenance
Battery Replacement
The disc lock uses LR44 batteries. When the alarm sound becomes weak or the device stops beeping upon locking, it's time to replace the batteries. Use the provided Allen key to open the battery compartment, typically located on the side or bottom of the lock. Replace all batteries with new ones, ensuring correct polarity, then reassemble the compartment.

Image: A visual guide demonstrating the process of opening the disc lock with the L-key to access and replace the batteries.
Waterproofing
The YOHOOLYO Alarm Disc Lock is designed to be waterproof and weather-resistant. However, to ensure longevity, avoid prolonged submersion in water and wipe it dry after exposure to heavy rain.

Image: The disc lock covered in water droplets, visually confirming its waterproof design.
General Care
Keep the lock clean and free from dirt and debris. Periodically check the locking pin and mechanism for smooth operation. Lubricate with a small amount of graphite powder or a silicone-based lubricant if needed.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Alarm is too sensitive or goes off frequently without cause. | High sensitivity setting; minor vibrations. | The sensitivity has been upgraded to prevent false alarms from minor touches. If movement is detected, it will give a warning beep before the full alarm. Ensure the lock is placed on a stable part of the disc. |
| Alarm is not loud enough or does not activate. | Low batteries; sensor malfunction. | Replace batteries with new LR44 cells. Ensure the lock is properly armed (single beep upon locking). If the issue persists, contact customer support. |
| Lock mechanism is stiff or difficult to engage/disengage. | Dirt/debris in mechanism; lack of lubrication. | Clean the locking mechanism. Apply a small amount of graphite powder or silicone-based lubricant to the keyhole and locking pin. |
| Battery life is shorter than expected. | Frequent alarm triggers; environmental factors. | The waterproof level has been improved to enhance battery life. Ensure the lock is not exposed to excessive moisture or frequent, unnecessary vibrations that trigger the alarm. Batteries typically last six months or longer. |
Specifications
| Feature | Detail |
|---|---|
| Brand | YOHOOLYO |
| Model Number | LK603 |
| Alarm Volume | 110 dB |
| Locking Pin Diameter | 7 mm |
| Material | All metal construction |
| Special Features | Waterproof, Crash-resistant, Motion Sensor with 5-second delay, Rust-resistant, Weather-resistant |
| Batteries | LR44 (6 internal, 6 backup) |
| Item Weight | 12.3 ounces |
| Product Dimensions | 3 x 2.8 x 1 inches |
| Country of Origin | China |
Warranty Information
YOHOOLYO products are manufactured to high-quality standards. For specific warranty details and terms, please refer to the product packaging or contact YOHOOLYO customer support directly. Keep your purchase receipt as proof of purchase for any warranty claims.
Support
For further assistance, technical support, or inquiries regarding your YOHOOLYO Alarm Disc Lock, please visit the official YOHOOLYO website or contact their customer service department. Contact information can typically be found on the product packaging or the brand's online store.
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