Introduction
Thank you for choosing the VASTFIRE FY-336 Rechargeable Bicycle Light. This device is designed to enhance your cycling safety and visibility with its powerful 1000-lumen output, integrated 130dB safety horn, and convenient USB charging/power bank functionality. This manual provides detailed instructions for proper installation, operation, maintenance, and troubleshooting to ensure optimal performance and longevity of your product.
Package Contents
Please inspect the package contents to ensure all items are present and in good condition:
- 1 x VASTFIRE FY-336 Bicycle Headlight
- 1 x Mounting Bracket
- 1 x Wired Remote Switch (for horn and light control)
- 1 x USB Charging Cable
- 1 x Rear Taillight
- 1 x User Manual
Video: Unboxing the VASTFIRE FY-336 Bicycle Light. This video demonstrates the contents of the package, including the headlight, mounting accessories, and cables.
Setup
Follow these steps to properly install your bicycle light system:
- Headlight Installation: Attach the mounting bracket to your bicycle's handlebar. Ensure it is securely fastened and positioned to provide optimal forward illumination. Slide the VASTFIRE headlight onto the bracket until it clicks into place.
- Remote Switch Connection: Connect the wired remote switch to the designated port on the headlight. Secure the remote switch to a convenient location on your handlebar for easy access during riding.
- Rear Taillight Installation: Mount the included rear taillight to your bicycle's seat post. Ensure it is visible from the rear and securely attached.

Image: Quick installation of the VASTFIRE bicycle headlight onto a handlebar mount. The image shows the headlight being slid onto its bracket, indicating a tool-free installation process.
Video: Installation of the VASTFIRE Bicycle Light and Taillight. This video demonstrates the step-by-step process of mounting both the front headlight and the rear taillight, as well as connecting the remote switch.
Operating Instructions
The VASTFIRE FY-336 features dual switches for comprehensive control over lighting and horn functions.
Headlight Operation
- Power On/Off: Press and hold the power button for two seconds to turn the light on or off.
- Main Light Modes (Power Button): Short press the power button to cycle through 3 main lighting modes: High Beam, Low Beam, and Full Brightness (High Beam + Low Beam).
- Auxiliary Light Modes (Light Button on Remote Switch): Short press the dedicated light button on the remote switch to cycle through 5 auxiliary lighting modes: Strong Light, Low Light, Fast Flash, SOS, and Slow Flash.
Horn Operation
- Activate Horn: Press the horn button on the wired remote switch to activate the 130dB safety horn.

Image: VASTFIRE bicycle light showing its various features including dual switch design, 8 light modes, 130dB horn, and waterproof rating. This image highlights the control interface and key functionalities.

Image: VASTFIRE bicycle light in use during night cycling and camping scenarios. The image illustrates the light's effectiveness in different dark environments, including road illumination and as a portable light source.
Charging and Power Bank Function
The VASTFIRE FY-336 is equipped with a 4400 mAh battery and USB charging capabilities, also functioning as a power bank.
Charging the Headlight
- Connect the provided USB charging cable to the headlight's input port and to a USB power source (e.g., computer, power bank, wall adapter).
- The indicator lights on the headlight will flash during charging and remain solid when fully charged.
- The 4400 mAh battery provides an operating time of 5 to 12 hours, depending on the selected light mode.
Power Bank Function
- The headlight features a USB output port, allowing it to be used as an emergency power bank to charge mobile phones or other USB-powered devices.
- Simply connect your device's charging cable to the headlight's USB output port.

Image: VASTFIRE bicycle light showing USB smart charging options from various sources like notebook, power bank, plug, and car. This image illustrates the versatility of the charging methods.

Image: VASTFIRE bicycle light being used as a power bank to charge a smartphone via its USB output port. This image demonstrates the USB output design for charging external devices.
Maintenance
To ensure the longevity and optimal performance of your VASTFIRE bicycle light, follow these maintenance guidelines:
- Cleaning: Wipe the light and its components with a soft, damp cloth. Do not use abrasive cleaners or solvents.
- Water Resistance: The light is rated IPX6 waterproof, meaning it is protected against powerful water jets. While it can withstand rain, avoid submerging it in water. Ensure the USB port cover is securely closed when not in use to maintain water resistance.
- Battery Care: For prolonged battery life, charge the device regularly, even if not in frequent use. Avoid completely draining the battery before recharging. If storing for a long period, charge it every 3 months.
- Storage: Store the light in a cool, dry place away from direct sunlight and extreme temperatures.

Image: VASTFIRE bicycle light being splashed with water, demonstrating its life-class waterproof feature. This image confirms the light's ability to function in rainy conditions.
Troubleshooting
If you encounter any issues with your VASTFIRE bicycle light, refer to the following common problems and solutions:
- Light Not Turning On:
- Ensure the battery is charged. Connect the light to a power source and check if the charging indicators activate.
- Press and hold the power button for at least 2 seconds to ensure it's not a short press.
- Horn Not Working:
- Check the connection of the wired remote switch to the headlight. Ensure it is firmly plugged in.
- Ensure the light is powered on. The horn typically requires the main unit to be active.
- Charging Issues:
- Verify that the USB cable is not damaged and is properly connected to both the light and the power source.
- Try a different USB cable or power adapter.
- Light Output is Dim:
- The battery level may be low. Recharge the light fully.
- Ensure the lens is clean and free from dirt or obstructions.
Specifications
| Brand | VASTFIRE |
| Model | FY-336 |
| Light Source | 4 x T6 LED |
| Lumen Output | 1000 Lumens |
| Horn Decibels | 130 dB |
| Battery Capacity | 4400 mAh (2 x 18650 Lithium Batteries) |
| Operating Time | 5-12 hours (depending on mode) |
| Charging Port | Micro USB Input |
| Output Port | USB-A Output (Power Bank Function) |
| Water Resistance | IPX6 (Waterproof) |
| Material | Aluminum |
| Mounting Type | Handlebar Mount |

Image: Diagram showing the dimensions of the VASTFIRE bicycle headlight: 116mm length, 42mm height, and 44mm width. This provides a visual reference for the product's size.
Warranty and Support
VASTFIRE is committed to providing high-quality products. For any warranty claims, technical support, or product inquiries, please contact your retailer or visit the official VASTFIRE website. Keep your purchase receipt as proof of purchase for warranty services.





