DARKBEAM T25 Bike Tail Light User Manual

1. Introduction

This manual provides essential information for the safe and effective use of your DARKBEAM T25 Bike Tail Light. Please read these instructions thoroughly before operation and retain for future reference.

The DARKBEAM T25 is a compact, high-visibility bicycle taillight designed to enhance rider safety during night riding and low-light conditions. It features an LED display for battery status, multiple lighting modes, intelligent braking detection, and a durable, waterproof design.

2. Safety Information

• Always ensure the taillight is securely mounted and fully charged before each ride.
• Do not look directly into the light beam to avoid temporary vision impairment.
• Clean the light regularly to maintain optimal visibility. Use a soft, damp cloth.
• Operating the bicycle taillight does not replace the need for other safety measures, such as wearing reflective clothing or using additional lighting.
• Adhere to all local traffic laws and regulations regarding bicycle lighting.

3. Package Contents

Verify that all items are present in your package:

• DARKBEAM T25 Bike Tail Light (battery included)
• Mount x 2 (1 Seat bow, 1 Seat tube)
• Tie strap (for fixing the seat bow) x 3
• USB-C Charging Cable x 1
• User Manual x 1

4. Product Overview

The DARKBEAM T25 features a compact design with an integrated LED display and a single control button.

Figure 1: DARKBEAM T25 Bike Tail Light showing the LED display and USB-C port.

Key Features:

• LED Display Screen: Shows real-time battery level.
• USB-C Rechargeable: Convenient and fast charging.
• 6 Lighting Modes: Various options for visibility.
• IP55 Waterproof: Designed for use in various weather conditions.
• Intelligent Braking: Automatically increases brightness upon deceleration.
• Auto Sleep/Wake: Conserves battery by entering sleep mode after 30 seconds of inactivity and waking upon vibration.

5. Setup & Installation

The DARKBEAM T25 offers versatile mounting options to suit your bicycle setup.

Figure 2: Two primary mounting styles: saddle rail and seat post.

5.1. Seat Post Mounting

1. Select the appropriate position on your seat post.
2. Wrap the silicone strap of the seat post mount around the seat post.
3. Hook the strap securely into one of the slots on the mount.
4. Insert the taillight into the mount at a 45-degree angle and rotate it 45 degrees to the left or right until it clicks into place.

5.2. Saddle Rail Mounting

1. Secure the saddle rail mount to the saddle rails using the provided zip ties. Ensure it is tight and stable.
2. Insert the taillight into the mount at a 45-degree angle and rotate it 45 degrees to the left or right until it clicks into place.

6. Operating Instructions

6.1. Power On/Off

• To turn on: Press and hold the power button (located on the side) for approximately 2 seconds.
• To turn off: Press and hold the power button for approximately 2 seconds.

6.2. Changing Lighting Modes

Once the light is on, short press the power button to cycle through the 6 available lighting modes:

1. Stay On (Constant Light Mode)
2. Rapid Flash Mode
3. Breathing Flash Mode
4. Flash Mode
5. Flicker Mode
6. Single Flash Mode

The light features a mode memory function, meaning it will restart in the last used mode when turned on again.

Figure 3: Visual representation of the 6 available lighting modes.

6.3. Intelligent Braking and Sleep Function

• Brake Sensing: In normal mode, the taillight automatically detects rapid deceleration (braking) and increases its brightness to alert vehicles behind you.
• Auto Sleep: If the taillight remains stationary for 30 seconds after being turned on, it will enter a sleep mode to conserve battery.
• Auto Wake: The light will automatically wake up from sleep mode upon detecting vibration (movement).

Figure 4: Brake sensor in action, increasing brightness when deceleration is detected.

6.4. Charging Instructions

The DARKBEAM T25 is equipped with a USB-C charging port.

1. Locate the USB-C port on the side of the taillight, protected by a waterproof cover.
2. Gently open the waterproof cover.
3. Connect the provided USB-C cable to the taillight and the other end to any standard USB power source (e.g., power bank, laptop, USB adapter). Ensure the power supply voltage does not exceed 5V 2A.
4. The LED display will indicate charging status.
5. Charging time is approximately 2.5 hours.
6. Once fully charged, disconnect the cable and securely close the waterproof cover to maintain IP55 water resistance.

Figure 5: USB-C fast charging with various compatible devices.

7. Maintenance

7.1. Cleaning

To clean the taillight, wipe it with a soft, damp cloth. Do not use abrasive cleaners or solvents, as these may damage the device.

7.2. Storage

When not in use for extended periods, store the taillight in a cool, dry place. It is recommended to charge the battery every 3-6 months to prolong its lifespan.

7.3. Water Resistance

The DARKBEAM T25 has an IP55 water resistance rating, meaning it is protected against dust ingress and low-pressure water jets from any direction. Ensure the USB-C port cover is always securely closed to maintain water resistance.

Figure 6: The taillight is designed to withstand rain and splashes.

8. Troubleshooting

• Light not turning on: Ensure the battery is charged. Press and hold the power button for 2 seconds.
• Light not charging: Check the USB-C cable and power source connection. Ensure the charging port is clean and free of debris.
• Light not responding to movement (Auto Wake): Ensure the light is not in sleep mode. If it is, simply move the bike to activate it.
• Light falling off mount: Re-check installation steps to ensure the mount is securely fastened and the light is properly clicked into the mount.

9. Specifications

10. Warranty and Support

The DARKBEAM T25 Bike Tail Light comes with a standard manufacturer's warranty against defects in materials and workmanship. For warranty claims, technical support, or any questions regarding your product, please contact DARKBEAM customer service through the retailer where the product was purchased.