The Shimano RD-9070 [paid link] rear derailleur is part of the high-performance Dura-Ace Di2 groupset, designed for electronic precision shifting. As a fully electronic derailleur, it eliminates mechanical cable stretch issues, ensuring accurate gear changes with minimal maintenance. However, proper installation and routine upkeep are crucial to maintain its top-tier performance.
This guide covers the full process of installing, adjusting, and maintaining the Shimano RD-9070 [paid link] rear derailleur. Whether you’re upgrading your bike or troubleshooting shifting issues, this article provides expert-level [paid link] guidance to keep your drivetrain running flawlessly.
Tools Required [paid links]
- Allen wrenches
- Torque wrench (for precise tightening)
- Di2 E-Tube wiring tool
- Shimano Di2 firmware updater or E-Tube Project app
- Bike stand [paid link]
- Chain tool
- Degreaser and chain lubricant
Step-by-Step Installation Guide
Installing the Shimano RD-9070 [paid link] is straightforward, but precision is key. Follow these steps for a smooth setup:
1. Mounting the Derailleur
- Shift the chain to the smallest rear cog.
- Use a 5mm Allen key to secure the derailleur to the derailleur hanger.
- Tighten the fixing bolt to 8-10 Nm to ensure a secure fit.
- Ensure the B-screw is properly positioned to provide clearance between the upper pulley and the cassette.
2. Connecting the Di2 Wiring
- Plug the E-Tube wire into the rear derailleur’s connection port.
- Route the wire through the frame, ensuring it’s properly secured to prevent damage.
- Connect the wire to the junction box.
- Test the connection by turning on the Di2 system and pressing the shift buttons to see if the derailleur responds.
3. Pairing and Initial Firmware Check
- Use the Shimano E-Tube Project app to check for firmware updates.
- If an update is available, install it to ensure the best shifting performance.
- Verify that the derailleur is recognized by the Di2 system.
Adjustment Process for Precise Shifting
Even with electronic shifting, fine-tuning is necessary to achieve optimal performance.
1. Set the Low and High Limit Screws
- The high-limit screw (H) controls how far the derailleur moves towards the smallest cog.
- The low-limit screw (L) sets the range for the largest cog.
- Use a 2mm gap between the upper jockey wheel and the cassette teeth to prevent excessive noise.
2. Adjust the B-Screw for Proper Chain Gap
- The B-screw controls derailleur clearance from the cassette.
- Adjust it to ensure 1-3mm of clearance between the upper pulley and the largest cog.
3. Fine-Tune Indexing via Di2 Micro-Adjustment
- Shift to the middle cog and enter adjustment mode by holding the function button.
- Use the shift buttons to micro-adjust the derailleur position until shifts feel precise and quiet.
- Exit adjustment mode and test shifting under load.
Routine Maintenance for Long-Term Performance
Proper maintenance extends the lifespan of your Shimano RD-9070 and ensures flawless operation.
1. Keep the Derailleur Clean
- Wipe down the derailleur after every ride, especially in wet or muddy conditions.
- Use a degreaser to remove grime from the jockey wheels.
2. Inspect and Replace Worn Components
- Check the jockey wheels for wear and replace them if they show excessive play.
- Inspect the Di2 wiring for any fraying or damage.
3. Update Firmware Regularly
- Connect to the Shimano E-Tube Project app to check for the latest firmware updates.
- Updating ensures the best shifting performance and bug fixes.
Troubleshooting Common Issues
Even with electronic precision, problems can arise. Here are some common issues and solutions:
1. Delayed or Unresponsive Shifting
- Ensure the battery is charged.
- Check Di2 wiring connections; unplug and replug them securely.
- Update firmware to resolve potential software glitches.
2. Skipping Gears or Poor Indexing
- Enter micro-adjustment mode and fine-tune the derailleur’s alignment.
- Check the limit screws to ensure they are correctly set.
3. Chain Dropping Off the Cassette
- Ensure the B-screw is adjusted properly for correct chain gap.
- Check for excessive wear on the cassette or chain.
Optimizing Performance
To get the best performance from your Shimano RD-9070, follow these expert tips:
- Keep Your Chain Clean – A clean chain shifts more smoothly and extends component lifespan.
- Use Shimano-Approved Lubricants – The right lube reduces wear and keeps shifting crisp.
- Check for Compatibility Before Upgrading – If switching to a larger cassette, ensure your derailleur can handle it.
- Fine-Tune for Your Riding Style – Use Di2’s micro-adjustment features to dial in perfect shifts.
Comparing the Shimano RD-9070 to Other Models
How does the RD-9070 stack up against newer or competing models?
| Feature | Shimano RD-9070 | Shimano RD-R9150 [paid link] (Next Gen) | SRAM eTap AXS |
|---|---|---|---|
| Shifting Type | Electronic | Electronic | Wireless Electronic |
| Weight | 217g | 204g | 308g |
| Max Cassette Size | 28T | 30T | 36T |
| Firmware Updates | Yes (Wired) | Yes (Bluetooth) | Yes (Wireless) |
Conclusion
The Shimano RD-9070 rear derailleur offers top-tier electronic shifting with incredible precision. With proper installation, fine-tuning, and regular maintenance, you can ensure it performs at its best for years to come. Follow this guide to set up your derailleur correctly and troubleshoot any issues that arise.
Keep your drivetrain in peak condition, and enjoy smooth, effortless shifting every ride!