Shimano Road Components Compatible with GRX Gravel

GRX: High Compatibility with Road Components

Shimano’s gravel-specific component group, GRX, is derived from road bike components, making it highly compatible with road bike parts.

Specifically, for drivetrain components, GRX is officially compatible with road groupsets of the same speed (number of gears) from the most recent two generations. Chains and cassettes can also be shared with road components as long as they match in speed.

Key Points When Mixing with Road Components

Match Components with the Same Number of Speeds

When mixing GRX with road components, the most important rule is to use parts with the same number of speeds (gears).

GRX has the following five lineups:

• GRX 12-speed Di2
• GRX 12-speed (mechanical)
• GRX 11-speed Di2
• GRX 11-speed (mechanical)
• GRX 10-speed (mechanical)

These are compatible with Shimano road groupsets starting from TIAGRA and above, depending on the generation.

Below is the specific compatibility chart:

If you use GRX brakes, keep in mind that all GRX models are hydraulic disc brakes only. Therefore, you must also use hydraulic-compatible STI levers from the road lineup for compatibility.

Note that Shimano’s 10-speed components include both the “new 10-speed” like TIAGRA 4700 and the “old 10-speed” like ULTEGRA 6700 and 105 5700. GRX 10-speed is only compatible with the “new 10-speed” (TIAGRA 4700 series).

Of course, even if the number of speeds matches, Di2 (electronic) and mechanical components cannot be mixed.

Pay Attention to Rear Derailleur Capacity

Shimano’s road bike components are designed with closely spaced gear ratios in mind, so their rear derailleurs have a smaller maximum cog size and total capacity compared to MTB components.

While mid-cage (GS) models are available in recent rear derailleurs, gravel bikes often use wide-range cassettes like 11-42T or 10-51T, similar to MTB setups. These setups often exceed a maximum cog size of 40T, which road-oriented GS derailleurs cannot handle.

If you’re planning to use a wide-range cassette with a largest cog over 36T, it’s best to stick with a GRX rear derailleur.

All GRX STI Levers Are Hydraulic Disc Brake Only

Another important point: all STI levers in the GRX lineup are exclusively for hydraulic disc brakes. There are no GRX STI levers designed for mechanical brakes.

Shimano road bikes may use either mechanical or hydraulic disc brakes. Mechanical brakes physically pull a cable to close the caliper, while hydraulic brakes use oil pressure in the hose. Because of their fundamentally different mechanisms, they are not interchangeable.

Also, Shimano does not offer hydraulic rim brakes in their road component lineup, so GRX components are not compatible with rim brakes either.

If you’re converting a rim brake road bike to a disc brake setup, you’ll need not only new wheels but also a disc brake-compatible frame. In many cases, this conversion can cost nearly as much as buying a complete new bike.

If you’re currently riding a rim brake road bike and want to convert it into a gravel bike using GRX components, using a compatible road STI lever instead of a GRX STI lever can save you a lot on replacement costs.

Road STI Levers Compatible with GRX Components

Here are the road STI levers that are compatible with each GRX component group:

Shimano STI lever model numbers follow a pattern:

• Add 50 to the base model for Di2 (e.g., ST-9100 → ST-9150)
• Add 20 for hydraulic brake compatibility (e.g., ST-R7000 → ST-R7020)
• Add 5 for small hand versions (e.g., ST-R7020 → ST-R7025)

So you can remember that:

• Numbers in the 70s = Di2 + Hydraulic
• Numbers in the 20s = Mechanical + Hydraulic

*Note: ST-R785, ST-RS685, ST-RS505, and ST-RS405 are exceptions to this rule.

If you’d like to use a mechanical shift + mechanical brake STI lever not listed above (e.g., ST-R7000 for 105) with GRX components, you can still use it—but only if you use a mechanical disc brake caliper.

In this case, you can use Shimano’s BR-RS303, or a third-party option like Growtac’s EQUAL (though not officially supported by Shimano), to combine GRX components with a road mechanical STI lever.

Compatibility with Road Components for GRX

Compatibility Between GRX and Road-DURA-ACE

The Shimano GRX for gravel and the DURA-ACE for road bikes are compatible with the 12-speed DURA-ACE R9200 series, and the 11-speed DURA-ACE 9000 and R9100 series. Initially, the R9200 series, which is Di2 12-speed, was not compatible with the GRX as GRX did not have a 12-speed system. However, with the introduction of the 12-speed GRX in 2024, compatibility has been established.

1. DURA-ACE R9270 series => Compatible with GRX Di2 12-speed
2. DURA-ACE R9150 series => Compatible with GRX Di2 11-speed
3. DURA-ACE R9100 series, 9000 series => Compatible with GRX 11-speed

Note: When using GRX brake parts, only DURA-ACE hydraulic-compatible parts are compatible.

Compatibility Between GRX and Road-ULTEGRA

The Shimano GRX for gravel and the ULTEGRA for road bikes are compatible with the ULTEGRA R8000 and 6800 series. Similar to DURA-ACE, when the R8100 series was released, GRX did not have a 12-speed Di2. However, with the 12-speed GRX released in 2024, compatibility has been established.

1. ULTEGRA R8170 series => Compatible with GRX Di2 12-speed
2. ULTEGRA R8050 series, 6870 series => Compatible with GRX Di2 11-speed
3. ULTEGRA R8000 series, 6800 series => Compatible with GRX 11-speed

Note: When using GRX brake parts, only ULTEGRA hydraulic-compatible parts are compatible.

Compatibility Between GRX and Road-105

The Shimano GRX for gravel and the 105 for road bikes are compatible with the 105 R7100 series (Di2 and mechanical), R7000 series, and 5800 series.

Initially, the GRX 12-speed series only offered mechanical shifting, but with the release of the GRX Di2 12-speed, it became possible to combine 12-speed components with either Di2 or mechanical 105. When assembling mechanically, only the 105 R7100 series, which is the only 12-speed mechanical lineup for road bikes, is compatible (STI lever, front/rear derailleurs, cassette, crankset, and brake calipers).

1. 105 R7150 series => Compatible with GRX Di2 12-speed
2. 105 R7100 series => Compatible with GRX 12-speed
3. 105 R7000 series, 5800 series => Compatible with GRX 11-speed

Note: When using GRX brake parts, only 105 hydraulic-compatible parts are compatible.

Compatibility Between GRX and Road-TIAGRA

The Shimano GRX for gravel and the TIAGRA for road bikes are only compatible with the TIAGRA 4700 series and GRX 10 combination. The TIAGRA 4600 series, being an older 10-speed, is not compatible.

1. TIAGRA 4700 series => Compatible with GRX 10-speed

Note: When using GRX brake parts, only TIAGRA hydraulic-compatible parts are compatible.

GRX and Road-Derailleur Compatibility

The GRX and road bike derailleurs are generally compatible if they have the same speed. As long as the derailleur’s capacity (front, rear, total) is within the limits, you can use older model sprockets.

Note that the latest GRX 12-speed sprockets require special attention.

Sprockets labeled “R” (CS-R0000 series) are compatible with road bike wheels and the HG spline L freehub (Shimano HG 11-speed), while the “M” labeled sprockets (CS-M0000 series) are only compatible with Microspline freehubs, which may require wheel replacements.

Compatibility of GRX Cranks, Chainrings with Road Cranksets

The GRX cranks follow the Shimano Hollowtech II standard, meaning that if you use a Hollowtech II bottom bracket, GRX cranks can be swapped with Shimano road cranks.

While GRX chainrings and front derailleurs are compatible with 10-12-speed road components, Shimano officially states that only GRX components are officially compatible. However, front shifting compatibility is less critical, meaning there may be non-official compatibility in certain cases.

Chainrings within the GRX system are interchangeable among GRX models.

However, note that GRX cranks are not compatible with some road cranks. For instance, the GRX front double cranks FC-RX810-2 and FC-RX600-11 have a 4-arm PCD110, which is the same as Shimano’s road front double cranks, but due to the unique shape of the GRX chainrings, you cannot fit road 4-arm PCD110 chainrings onto the GRX crank.

For example, swapping the FC-R7000 chainrings from the 105 crankset with the FC-RX600-11’s 46-30T chainring to convert it into a “gravel gear” setup is not possible without replacing the entire FC-RX600-11 crankset.

Shimano’s GRX for gravel is highly compatible with road bike components. Just remember to:

1. Pair the same speeds together
2. Pay attention to hydraulic systems
3. Be mindful of maximum cassette capacity
4. Consider freehub standards (spline compatibility)

After buying a new road bike, you may choose to combine your existing road bike with GRX components to convert it into a gravel bike, expanding your cycling options.

Frequently Asked Questions About Combining Shimano GRX and Road Components