User Hub R7 Wiki
V2.0
⚙️ Ch. 3

Tuning

Shifting tuning and lever settings

Tuning Workflow Overview

Estimated time: 45–60 min
Progress
0 / 4 Steps
①

Limit-Screw Calibration

Set the H, L, and B screws to define the rear derailleur's physical travel envelope

  • ✓ H screw — High-limit stop
  • ✓ L screw — Low-limit stop
  • ✓ B screw — Pulley tension

Safety Warning

Loose H/L screws can let the chain drop, damaging the wheel or frame!

Tools Required

  • 2 mm hex key
  • Bike repair stand
  • Ruler or caliper (to measure B-screw gap)

Adjustment Sequence

  1. H screw: Shift to the smallest cog, align the guide pulley
  2. L screw: Shift to the largest cog, align the guide pulley
  3. B screw: Measure pulley-to-cog gap (5–7 mm)
②

Electronic System Calibration

Configure Semi-Sync and micro-tune via the WHALEROAD App or shift levers

  • ✓ Bluetooth connection
  • ✓ Semi-Sync setup
  • ✓ Gear micro-adjust

App Calibration (Recommended)

  1. Open the WHALEROAD App and connect to the rear derailleur
  2. Go to "System Settings" → "Shift Calibration"
  3. Toggle Semi-Sync on or off
  4. Micro-adjust each cog until the chain lines up perfectly

Lever Manual Calibration

  1. Long-press the function button for 5 s to enter pairing mode
  2. Hold both paddle shifters + function button for 3 s
  3. Use the left paddle to toggle Semi-Sync on/off
  4. Long-press the function button to save and exit
③

Shift Performance Validation

Sweep every cog to confirm shifting accuracy and response time

  • ✓ Upshift test
  • ✓ Downshift test
  • ✓ Load test

Test Sequence

  1. Upshift test: Move from smallest to largest cog, one at a time
  2. Downshift test: Move from largest to smallest cog, one at a time
  3. Rapid fire: Trigger multiple shifts in succession to test responsiveness
  4. Load test: Verify under real riding conditions

Pass Criteria

  • Every cog engages cleanly with no skipping
  • Shift response < 0.5 s
  • No abnormal noise or friction
  • Semi-Sync functions correctly (if enabled)
④

Final Check & Documentation

Save calibration parameters, log tuning data, and back up your settings

  • ✓ Save settings
  • ✓ Log data
  • ✓ Firmware update

Save & Back Up

  • Save the current configuration in the App
  • Record micro-adjust values for each cog
  • Screenshot your Semi-Sync settings

Firmware Check

Check for available firmware updates. Running the latest version ensures peak performance.

Limit-Screw Calibration

Critical Step

The H, L, and B limit screws set the rear derailleur's physical travel envelope—foundational to every precise shift

H

High-Limit Screw

H Screw (High Limit)
Function

Restricts outward derailleur travel toward the smallest cog, preventing the chain from dropping into the spokes

1
Shift into position Move the chain onto the smallest cog
2
Check alignment Center the upper guide pulley with the smallest cog
3
Adjust the screw
Clockwise: moves inward Counter-clockwise: moves outward

Too loose and the chain can fall into the spokes, destroying the wheel!

L

Low-Limit Screw

L Screw (Low Limit)
Function

Restricts inward derailleur travel toward the largest cog, preventing the chain from jamming against the frame

1
Shift into position Move the chain onto the largest cog
2
Check alignment Center the upper guide pulley with the largest cog
3
Adjust the screw
Clockwise: moves outward Counter-clockwise: moves inward

Too loose and the chain can jam into the frame, wrecking the drivetrain!

B

Pulley-Tension Screw

B-Tension Screw
Function

Controls the gap between the upper guide pulley and the cassette, directly affecting shift speed and smoothness

1
Shift into position Move the chain onto the largest cog
2
Measure the gap Pulley-to-cog tip distance: 5–7 mm
Ideal: 6 mm
3
Adjust the screw
Clockwise: gap ↑ Counter-clockwise: gap ↓

Too large a gap slows shifting; too small creates noise

Electronic Calibration

Configure Global Offset and Fine-Tunning for your wireless drivetrain through the WHALEROAD App

App Calibration (Recommended)

1
Connect the system

Enable Bluetooth on your phone, open the WHALEROAD App, and connect to the rear derailleur

2
Enter the rear derailleur page

On the App home screen, tap the connected rear derailleur to enter its settings page

3
Set calibration mode
4
Global Offset

Adjusts the entire derailleur position as a whole. Use this when all gears need uniform shifting correction.

+ Positive values move the derailleur outward
− Negative values move the derailleur inward
0
≈ 0.1 mm per step
Fine-Tunning

Allows precise adjustment per individual cog. Use this when specific gears are noisy or shift poorly.

1 Select each cog individually in the App
2 Adjust offset per cog using +/- buttons
3 Work through each cog systematically
0
Current cog offset

Shift Performance Validation

After mechanical and electronic adjustments, sweep the entire cassette to verify everything

0 / 4 Tests Complete

Upshift Test

Smallest to largest cog, one at a time

Tap to mark complete

Downshift Test

Largest to smallest cog, one at a time

Tap to mark complete

Rapid Fire

Trigger multiple shifts in succession

Tap to mark complete

Load Test

Verify shifting under real riding load

Tap to mark complete

✓ Pass Criteria

Every cog engages cleanly with no skipping
Shift response < 0.5 s
No abnormal noise or friction
No chain rub in extreme gear combinations

Troubleshooting

Quick diagnosis and fixes for the most common issues

Skipping / Inaccurate Shifts

Chain jumps or fails to settle on the target cog
1
Inspect limit screws

Confirm H and L screws are set correctly and the pulley aligns with the cogs

2
Check B-screw gap

Measure pulley-to-cog distance; it should be 5–7 mm

3
Micro-tune electronically

Use the App to fine-tune offset for each cog

If the issue persists: Inspect chain and cassette wear; replace if beyond service limit

Noise / Friction

Abnormal sound when shifting or in certain gears
1
Pinpoint the noise

Specific cog → micro-adjust that cog; all cogs → check B screw

2
Clean the pulleys

Remove grime and old lube from the pulley wheels

3
Check pulley bearings

Spin the pulleys by hand; they should turn freely with no binding

Slow Shifting Response

Delay or no reaction after pressing the lever
1
Check B-screw gap

An oversized gap increases cable/motor travel; reduce it slightly

2
Check for interference

Move away from strong electromagnetic sources and re-pair the levers

Cannot Reach Certain Gears

Highest or lowest cog will not engage
1
Inspect limit screws

H screw controls the highest cog; L screw controls the lowest cog

2
Check App settings

Make sure the cassette size in the App matches your actual cassette

3
Re-run calibration

Perform a full electronic calibration from start to finish

Battery & System Status

Read battery indicators and perform system maintenance

Battery Status

75% ≈ 1,200 km range
≥ 20% Normal
< 20% Charge now

LED Indicators

Solid green Normal operation
Solid red Critical battery
Green blinking Pairing mode