User Hub R7 Wiki
V2.0
🛠️ Ch. 4

Maintenance

Brake system bleeding and venting

Maintenance Schedule

Regular care that extends system life

After Every Ride

  • Verify shifting response is crisp and immediate
  • Check LED indicator colors for status
  • Wipe sweat and dust from lever surfaces

Monthly Inspection

  • Inspect brake pad wear levels
  • Assess chain lubrication condition
  • Confirm battery charge status

Every Quarter / 500 km

  • Bleed brakes and refresh hydraulic fluid
  • Deep-clean the drivetrain
  • Inspect pulley wheel bearings

Brake Bleeding

Pro Procedure

Replace brake fluid and purge air regularly to maintain peak braking performance

Safety Warning

Bleeding requires specialized tools and experience. We strongly recommend visiting an authorized WHALEROAD service center. Improper procedure can lead to total brake failure.

Tools Required

Dedicated bleed kit
Compatible mineral brake fluid
7 mm wrench
8 mm open-end wrench
Syringe
Catch bottle
1
Preparation
  • Secure the bike on a repair stand, level and stable
  • Remove the rear wheel for caliper access
  • Position a drip tray and have shop towels ready
  • Wear safety glasses and nitrile gloves
2
Drain Old Fluid
  • Attach a bleed hose and catch container to the caliper bleed port
  • Use a 7 mm wrench to gently open the bleed screw
  • Squeeze the brake lever to push out old fluid
  • Note: mineral oil is toxic — avoid skin contact
3
Inject New Fluid (Bottom-Up)
  • Close the caliper bleed screw
  • Fill the lever reservoir with fresh brake fluid
  • Squeeze the lever slowly to drive fluid downward
  • Repeat until the line is completely filled with new fluid
4
Purge Air
  • Keep the reservoir topped up at all times
  • Pump the brake lever rapidly 10–15 times
  • Pull the lever to the bar and release it slowly each time
  • Watch for air bubbles rising in the reservoir
5
Final Check
  • Torque all screws to spec (7 mm screw: 6–8 N·m)
  • Clean any spilled fluid from components and paint
  • Test lever feel — it should be firm with no sponginess
  • Reinstall the wheel and perform a controlled brake test

Component Replacement Guidelines

Know exactly when to replace critical wear parts

Chain

Replace When Elongation > 0.75%
  • Chain-checker gauge reads beyond 0.75%
  • Shifting feels sluggish or chain skips under load
  • Visible rust, tight links, or surface damage

Cassette

Replace When Teeth visibly sharpened
  • Profile of favorite gears has changed to sharp hooks
  • New chain still skips on the cassette
  • Chain slips under power

Brake Pads

Replace When Thickness < 1.5 mm
  • Backing plate is approaching the rotor
  • Noise, reduced power, or inconsistent bite
  • Pad surface is glazed, cracked, or contaminated

Pulley Wheels

Replace When Tooth wear or seized bearing
  • Teeth have sharpened or chipped edges
  • Rotation feels rough or noisy
  • Wheel body has play or wobble

Storage & Transport

Protect precision electronics with proper handling

Long-Term Storage

  • Remove the rear derailleur battery and store it separately
  • Charge to 40–60% before storing
  • Avoid temperatures above 40 °C and humid environments
  • Check charge level every 3 months

Road Transit

  • Use a dedicated bike travel case or bag
  • Remove or shield the rear derailleur with a protector
  • Place padding between brake levers to prevent compression
  • Avoid storing the bike upside down or on its side

Air Travel

  • Rear derailleur battery must be carried in hand luggage (<100 Wh)
  • Power down the system before packing
  • Use battery terminal covers for insulation
  • Keep the product manual accessible for inspection