1. Safety Information
Operating a dirt bike can be dangerous if proper safety precautions are not followed. Always prioritize safety to prevent injury or damage.
- Always wear appropriate safety gear, including a helmet, eye protection, gloves, long pants, and sturdy boots.
- Ensure adult supervision for all youth riders.
- This dirt bike is designed for off-road use only. It is not street legal and should not be operated on public roads, sidewalks, or paved areas.
- Perform pre-ride inspections before each use to check brakes, tires, and controls.
- Do not operate the bike under the influence of alcohol or drugs.
- Keep hands, feet, and clothing away from moving parts.
2. Product Overview
The X-PRO 125cc Kids Dirt Bike is a robust youth dirt pit bike featuring a 4-speed semi-automatic transmission and large 14"/12" tires, designed for off-road adventures. It is equipped with a reliable Zongshen 125cc engine and a strong steel frame for durability and performance.



3. Setup and Assembly
The X-PRO 125cc Dirt Bike requires some assembly upon arrival. Please follow these steps carefully. It is recommended to have two people for assembly.
3.1 Unpacking
Carefully remove the dirt bike from its shipping crate. Inspect for any shipping damage before proceeding with assembly.


3.2 Assembly Steps
- Handlebar Installation: Attach the handlebar brackets securely. Ensure the handlebars are centered and tightened to the recommended torque specifications.
- Wheel Attachment: Install the front and rear wheels. Pay close attention to the orientation of the brake discs and ensure all axle nuts are properly tightened.
- Brake System Connection: Connect and adjust the brake levers and calipers. Verify proper brake function before riding.
- Number Plate and Fender Installation: Securely attach the front number plate and fenders.
- Fluid Checks: Check engine oil levels and add fuel. Refer to the specifications section for recommended fluid types.
- Final Inspection: Before the first ride, double-check all nuts, bolts, and fasteners for tightness. Ensure all cables are routed correctly and not pinched.
4. Operating Instructions
4.1 Starting the Engine
- Ensure the fuel valve is in the 'ON' position.
- If the engine is cold, set the choke lever to the 'ON' or 'START' position.
- Place the bike on a stable surface, preferably with the kickstand down.
- Firmly press down on the kick start lever until the engine starts.
- Once the engine starts, gradually return the choke lever to the 'OFF' position as the engine warms up.
4.2 Transmission (Semi-Automatic)
This dirt bike features a 4-speed semi-automatic transmission, meaning there is no clutch lever to operate. Shifting gears is done by simply pressing the gear shift lever with your foot.
- Shifting Up: Press the gear shift lever down with your foot to shift from neutral to 1st gear, then lift the lever up for 2nd, 3rd, and 4th gears.
- Shifting Down: Press the gear shift lever down repeatedly to downshift through the gears.
- The transmission is designed to allow shifting without manually operating a clutch.
4.3 Braking
The bike is equipped with disc brakes for effective stopping power.
- The front brake is operated by the lever on the right handlebar.
- The rear brake is operated by the foot pedal on the right side.
- Apply both brakes smoothly and simultaneously for optimal stopping performance. Avoid sudden, hard braking, especially on loose surfaces.
4.4 Riding Tips
- Always ride within your skill level and the bike's capabilities.
- Be aware of your surroundings and potential hazards.
- The maximum recommended weight for the rider is 165 pounds.
- Ensure the rider meets the minimum user height of 29 inches for safe operation.
5. Maintenance
Regular maintenance is crucial for the longevity and safe operation of your X-PRO 125cc Dirt Bike.
5.1 Routine Checks (Before Each Ride)
- Tires: Check tire pressure and inspect for wear or damage.
- Brakes: Verify proper function of front and rear brakes. Ensure levers and pedals have adequate free play.
- Chain: Check chain tension and lubrication. Adjust if necessary.
- Fasteners: Inspect all nuts, bolts, and fasteners for tightness.
- Fluids: Check engine oil level.
5.2 Scheduled Maintenance
- Engine Oil Change: Change engine oil after the first 5 hours of operation, then every 15-20 hours or seasonally, whichever comes first. Use recommended oil type (refer to specifications).
- Air Filter Cleaning: Clean the air filter every 10-15 hours of operation, more frequently in dusty conditions.
- Spark Plug Inspection: Inspect and clean the spark plug every 20-30 hours. Replace if worn.
- Chain Lubrication: Lubricate the drive chain every 5-10 hours of operation.
- Brake Pad Inspection: Check brake pad wear every 20-30 hours. Replace if worn beyond limits.
6. Troubleshooting
This section provides solutions for common issues you might encounter.
| Problem | Possible Cause | Solution |
|---|---|---|
| Engine won't start | No fuel, choke off (cold engine), fouled spark plug, carburetor issue | Check fuel level and fuel valve. Apply choke. Clean/replace spark plug. Inspect carburetor for blockages. |
| Loss of power | Dirty air filter, old fuel, spark plug issue, incorrect engine oil | Clean air filter. Drain old fuel and refill with fresh. Check/replace spark plug. Ensure correct oil type and level. |
| Brakes not effective | Worn brake pads, air in brake lines, loose cables | Inspect and replace brake pads. Bleed brake lines (professional recommended). Adjust brake cables. |
| Excessive vibration | Loose fasteners, unbalanced wheels, worn bearings | Check and tighten all fasteners. Inspect wheels and bearings for damage. |
If you encounter issues not listed here or if solutions do not resolve the problem, please contact qualified service personnel.
7. Specifications
| Feature | Specification |
|---|---|
| Bike Type | Kids Bike |
| Age Range (Description) | Kid, Youth |
| Brand | X-PRO |
| Number of Speeds | 4 |
| Color | Black |
| Wheel Size | 14 Inches (Front), 12 Inches (Rear) |
| Frame Material | Alloy Steel |
| Suspension Type | Front, Rear |
| Special Feature | Off-road |
| Included Components | Manual, Tool Kit |
| Brake Style | Disc |
| Item Weight | 123 Pounds |
| Maximum Weight Recommendation | 165 Pounds |
| Minimum User Height | 29 Inches |
| Bicycle Drivetrain Type | Semi-Automatic |
| Model Number | XB27B-125 |
8. Warranty and Support
8.1 Warranty Information
The X-PRO 125cc Kids Dirt Bike comes with a 1-month limited warranty. This warranty covers manufacturing defects under normal use. Please retain your proof of purchase for warranty claims. For specific details regarding coverage and exclusions, refer to the warranty documentation included with your product.
8.2 Customer Support
For technical assistance, parts inquiries, or any questions regarding your X-PRO 125cc Dirt Bike, please contact XPROUSA customer service. Contact information can typically be found on the X-PRO official website or through your original point of purchase. When contacting support, please have your model number (XB27B-125) and purchase details readily available.





