TTGO HZ-28ST Electric Bike User Manual

Important Safety Information

⚠️ Disclaimer: Please mind potential fire risk and strictly follow the instruction manual for charging and storage. While using the product, please wear protective equipment and fully comply with the applicable law and regulations.

• Always wear a helmet and appropriate safety gear when riding.
• Familiarize yourself with local laws and regulations regarding electric bicycles.
• Perform a pre-ride safety check before each use.
• Do not operate the bike under the influence of alcohol or drugs.
• Ensure all components are securely fastened before riding.

1. Product Overview

The TTGO HZ-28ST is a versatile electric bicycle designed for comfortable and efficient commuting and recreational riding. It features a 250W motor, a 36V 20Ah battery, and a 7-speed Shimano shifter, offering a maximum range of 100km and a top speed of 25km/h.

Figure 1: TTGO HZ-28ST Electric Bike (White Model)

Figure 2: TTGO HZ-28ST Electric Bike (Black Model)

2. Specifications

Figure 3: TTGO HZ-28ST Electric Bike Specifications Overview

Figure 4: TTGO HZ-28ST Electric Bike Dimensions

3. Setup and Assembly

Your TTGO HZ-28ST Electric Bike comes partially assembled. Follow these steps to complete the setup:

1. Unpacking: Carefully remove the bike and all components from the packaging. Retain packaging for future transport or storage.
2. Handlebar Installation:
   • Loosen the stem bolts and insert the handlebar into the stem.
   • Adjust the handlebar to a comfortable riding position (refer to Figure 4 for dimensions).
   • Ensure the brake levers and shifter are correctly oriented and tighten the stem bolts securely.
3. Front Wheel Installation:
   • Align the front wheel with the fork dropouts.
   • Insert the quick-release skewer or axle through the hub and tighten it securely.
   • Ensure the disc brake rotor is correctly seated within the caliper.
4. Pedal Attachment:
   • Identify the left (L) and right (R) pedals.
   • Thread the 'L' pedal counter-clockwise into the left crank arm.
   • Thread the 'R' pedal clockwise into the right crank arm.
   • Tighten both pedals firmly with a wrench.
5. Seat Post and Saddle:
   • Insert the seat post into the frame's seat tube.
   • Adjust the saddle height for comfortable pedaling (refer to Figure 4 for recommended height).
   • Secure the quick-release lever or bolt firmly.
6. Initial Battery Charge:
   • Before your first ride, fully charge the battery using the provided 3A charger.
   • Connect the charger to the battery port and then to a power outlet.
   • The charging indicator on the charger will show the charging status. A full charge typically takes 6-8 hours.
   • Do not overcharge the battery. Disconnect once fully charged.
   

   Figure 5: Battery Location and Specifications
7. Tire Inflation: Inflate tires to the recommended pressure indicated on the tire sidewall.
8. Brake Check: Test both front and rear brakes to ensure they are functioning correctly and provide adequate stopping power.

4. Operating Instructions

Familiarize yourself with the controls before your first ride.

Figure 6: Handlebar Controls

1. Power On/Off:
   • Press and hold the power button on the LCD display to turn the bike on or off.
   • The display will show speed, battery level, and pedal assist level.
2. Pedal Assist System (PAS):
   • The bike features 5 levels of pedal assist. Use the '+' and '-' buttons on the display control to adjust the assist level.
   • Higher levels provide more motor assistance.
3. Twist Throttle:
   • Gently twist the throttle on the right handlebar to engage motor power without pedaling.
   • The throttle provides power up to the maximum speed of 25km/h.
4. Gear Shifting:
   • Use the Shimano 7-speed shifter on the right handlebar to change gears.
   • Shift to a lower gear for easier pedaling on inclines and a higher gear for faster speeds on flat terrain.
   • Always shift gears while pedaling lightly to avoid damaging the drivetrain.
5. Braking:
   • The bike is equipped with mechanical disc brakes (160mm).
   • Apply both brake levers gently and evenly to slow down or stop.
   • Avoid sudden, hard braking, especially at high speeds or on loose surfaces.
6. Lights:
   • The bike has a 1.5W LED headlight and a 0.3W taillight.
   • Turn on the lights for visibility, especially during low-light conditions or at night. Refer to the display manual for specific light control.

5. Maintenance

Regular maintenance ensures the longevity and safe operation of your electric bike.

• Battery Care:
  • Charge the battery regularly, even if not in use, to maintain its health.
  • Store the battery in a cool, dry place, away from direct sunlight and extreme temperatures.
  • Do not expose the battery to water or excessive moisture.
  • Use only the original charger provided.
• Tires:
  • Check tire pressure before each ride and inflate to the recommended PSI.
  • Inspect tires for wear, cuts, or punctures regularly.
• Brakes:
  • Regularly check brake pads for wear and replace them when necessary.
  • Ensure brake levers are firm and responsive. Adjust cable tension if needed.
  • Keep disc rotors clean and free from oil or grease.
• Chain and Drivetrain:
  • Clean and lubricate the chain regularly, especially after riding in wet or dusty conditions.
  • Check for worn gears or chain links and replace as needed.
• General Cleaning:
  • Wipe down the bike frame with a damp cloth. Avoid using high-pressure washers directly on electrical components.
  • Keep all electrical connections dry and clean.
• Fasteners: Periodically check all bolts, nuts, and quick-release levers to ensure they are securely tightened.

6. Troubleshooting

Here are some common issues and their potential solutions:

• Bike not powering on:
  • Check if the battery is properly inserted and locked.
  • Ensure the battery is charged.
  • Verify all electrical connections are secure.
• Motor not assisting:
  • Check the pedal assist level on the display; ensure it's not set to '0'.
  • Ensure the battery has sufficient charge.
  • Check for any error codes on the LCD display.
• Brakes feel weak or spongy:
  • Inspect brake pads for wear; replace if necessary.
  • Check brake cable tension and adjust if loose.
  • Ensure disc rotors are clean and free of contaminants.
• Unusual noises during riding:
  • Check for loose components (e.g., fenders, rack, kickstand).
  • Inspect the chain and drivetrain for proper lubrication and alignment.
  • Listen for brake rub and adjust calipers if needed.

If you encounter persistent issues not covered here, please contact customer support.

7. User Tips

• Battery Range: The stated range of 110km is achievable under optimal conditions (flat terrain, low assist level, light rider). Actual range may vary based on terrain, rider weight, assist level, and weather conditions.
• Smooth Shifting: For smoother gear changes and to prolong drivetrain life, ease off the pedals slightly when shifting gears.
• Tire Choice: The Kenda 700C*45C tires are suitable for various terrains, as shown in Figure 7. Maintain proper tire pressure for optimal performance and comfort.

Figure 7: Shockproof Fork and Kenda Tires for Multi-Terrain Use

8. Warranty and Support

For warranty claims, technical support, or any questions regarding your TTGO HZ-28ST Electric Bike, please contact the seller, GUNAI Ride Store, directly. Information regarding return and refund policies can be obtained from the seller.