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Shimano GRX RD-RX820 rear derailleur

SHIMANO GRX RD-RX820 Rear Derailleur

$184.99

SHIMANO GRX RD-RX820 Rear Derailleur offers silent, secure shifting with adjustable chain stabilizer and SHIMANO SHADOW RD+ tech.

In stock

Free standard shipping Canada-wide over $100
30-day returns on eligible unused items
Ships from Guelph, Ontario

Decision guidance

Is this right for you?

Best For

Ideal for riders tackling rough and mixed terrain who require smooth, secure, and reliable rear shifting performance.

What to Know

Offers a stable and quiet ride feel by minimizing chain slap and drops through its adjustable chain stabilizer and ON/OFF switch for terrain adaptability.

Why We'd Choose It

Choose the GRX RD-RX820 for its advanced chain stabilizer system and SHIMANO SHADOW RD+ design that together deliver silent, secure, and smooth shifting across varied surfaces.

At a glance

Product facts

Use
Rough and mixed terrain cycling
Key feature
Adjustable chain stabilizer with SHIMANO SHADOW RD+ for secure shifting
Product Story

Product details

Reliable Shifting Performance

The SHIMANO GRX RD-RX820 Rear Derailleur ensures silent and secure shifting on rough terrain, thanks to its adjustable chain stabilizer that prevents chain slap and drops. The SHIMANO SHADOW RD+ technology enhances performance on mixed surfaces.

Wide Gear Compatibility

Compatible with 11-34T and 11-36T 12-speed cassettes, this derailleur offers a wide gear range for comfortable cadence across various terrains. The integrated chain stabilizer includes an ON/OFF switch to match the terrain for smooth surface rides.

Technical Specifications

  • Maximum front chainring difference: 17T
  • Top sprocket: Max. 11T/Min. 11T
  • Low sprocket: Max. 36T/Min. 34T
  • Total capacity: 42T

Key Specs

Specifications

Maximum Front Chainring Difference 17T Maximum allowable difference between front chainrings
Top Sprocket Size Max. 11T / Min. 11T Top sprocket size range supported
Low Sprocket Size Max. 36T / Min. 34T Low sprocket size range supported
Total Capacity 42T Total gear capacity supported
Questions & answers

Common questions

What technology does the GRX RD-RX820 use to improve shifting performance?

It uses SHIMANO SHADOW RD+ technology which enhances chain retention and provides silent, secure shifting on rough terrain.

Can the chain stabilizer be adjusted or turned off?

Yes, the derailleur features an adjustable chain stabilizer with an ON/OFF switch to match different terrain conditions.

What gear range is compatible with this derailleur?

It is compatible with 11-34T and 11-36T 12-speed cassettes, supporting a total capacity of 42T.

Delivery & Returns

What to expect

Shipping

Free standard Canada-wide shipping over $100 before tax.

Returns

45-day returns for eligible unused items.

Ships from

Ships from Guelph, Ontario
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