Shimano Spares Inner Plate - RD-M8120 - SGS
Best current price£12.94from eBay
Best offers
Shopping.co.uk recommended and popular offers
eBay£12.94Visit shop Shimano RD-M8120-SGS Inner Plate - Y3FX26000 Deore XT
Visit shopeBay£12.94Visit shop One Offer
1 offer from £12.94
View price history by clicking the chart icon.
eBayShimano RD-M8120-SGS Inner Plate - Y3FX26000 Deore XT
Free delivery in 1–3 days
£12.94
Visit shop
Product Information
Full details
The Shimano Spares Inner Plate for the RD-M8120-SGS derailleur is designed for dedicated mountain bikers and mechanics seeking to restore precise shifting performance to their Deore XT drivetrain. This genuine replacement component ensures that your derailleur cage maintains proper structural integrity and chain tension, though users should ensure their current derailleur is the exact SGS long-cage variant before attempting installation.
All features
| Model Part Number | RD-M8120 |
|---|---|
| Brand | SHIMANO |
Extended Product Information
FAQs
Is this compatible with the RD-M8100 derailleur?
No, this part is specifically engineered for the RD-M8120-SGS model.
Do I need special tools to replace this plate?
You will generally need a set of metric hex keys, specifically a 3mm or 4mm, depending on your pulley bolt configuration.
Does this plate come with replacement pulley wheels?
No, this is the inner plate only. Pulleys and bolts are sold separately.
Why is the SGS designation important?
SGS refers to the long-cage length. Using the wrong plate length will negatively impact shifting performance and chain tension.
Can I replace the inner plate without removing the chain?
While possible, it is highly recommended to remove the chain to gain better access to the derailleur cage bolts.
Troubleshooting
Shifting remains inconsistent after installation
Check that the pulley wheels are correctly seated and that the derailleur hanger is not bent.
Cage feels stiff or does not snap back
Ensure that the pivot points were cleaned and lubricated during reassembly and that bolts are not over-tightened.
Pros and Cons
Pros
- Ensures exact factory compatibility with the RD-M8120 derailleur
- Restores smooth and reliable shifting performance
- High-quality construction maintains structural rigidity
- Prevents drivetrain wear caused by misaligned derailleur cages
Cons
- Compatibility limited strictly to the SGS version of the RD-M8120
- Requires derailleur disassembly for installation
- Does not include mounting hardware or pulleys
Setup, Compatibility & Care
To install this inner plate, you must remove the rear derailleur from the bike and carefully dismantle the cage assembly. Ensure you organize the pulley wheels and their respective dust covers during removal, as these are reused with the new plate. Use a torque wrench to tighten cage bolts to manufacturer specifications to avoid stripping threads. Regular maintenance involves keeping the pulleys clean of mud and debris and ensuring the cage remains free of lateral play. This part is exclusively compatible with the Shimano RD-M8120-SGS rear derailleur.