STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop
STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

8 Bolts interface
AXS tooth/ non-AXS tooth support
38t- 58T

Upgrade your drivetrain with the STONE SRAM 8-Bolt Direct Mount Round Chainring, designed for SRAM road 8-bolt cranksets. Machined from premium 7075-T651 aluminum, this chainring features a 4mm inward offset, narrow-wide tooth design, and a lightweight round profile for reliable chain retention and smooth power transfer.

Available in AXS tooth profile for SRAM FlatTop chains and Non-AXS tooth profile for standard 9/10/11/12-speed non-FlatTop chains.


Key Features

  • Compatible with SRAM road 8-bolt direct mount cranksets
  • Available in AXS and Non-AXS tooth profiles
  • 4mm inward offset design
  • Round narrow-wide single chainring
  • CNC machined from 7075-T651 aluminum
  • 8mm thick aluminum plate construction
  • Anodized finish for corrosion and wear resistance
  • Tooth sizes available from 38T to 58T
  • Suitable for road, folding bike, and gravel setups
  • Multiple color options available
  • T20 installation, recommended torque: 4 Nm

Full Product Description

The STONE SRAM 8-Bolt Direct Mount Round Chainring is designed for riders who want a clean, efficient, and lightweight single-chainring setup for SRAM road 8-bolt cranksets.

Made from high-strength 7075-T651 aluminum, each chainring is precisely CNC machined to ensure excellent stiffness, durability, and accurate fitment. The narrow-wide tooth design helps improve chain retention, making it suitable for road, gravel, and folding bike applications.

This chainring uses a 4mm inward offset design. The actual inward offset is approximately 4.4mm, and the model is simplified as 4OF. This offset helps place the chainline closer to the frame, improving drivetrain efficiency when using larger cassette sprockets and reducing the chance of chain drop during backpedaling.


Tooth Profile Options

AXS Tooth Profile

Choose the AXS tooth profile if you are using:

  • SRAM AXS 12-speed FlatTop chain
  • SRAM T-Type chain
  • SRAM original FlatTop chain

The AXS tooth profile is designed for SRAM’s flat-top chain structure and provides proper engagement with SRAM AXS 12-speed road drivetrains.


Non-AXS Tooth Profile

Choose the Non-AXS tooth profile if you are using:

  • Standard 9-speed chains
  • Standard 10-speed chains
  • Standard 11-speed chains
  • Standard 12-speed non-FlatTop chains
  • Shimano 9/10/11/12-speed chains
  • SRAM 9/10/11/12-speed non-FlatTop chains
  • Most conventional chains

For Shimano 12-speed chains, we recommend replacing the original quick link with a KMC 12-speed quick link for better compatibility.


Compatibility

Crank Compatibility

Compatible with:

  • SRAM road 8-bolt direct mount cranksets
  • SRAM Rival 8-bolt cranksets
  • SRAM Force 8-bolt cranksets
  • SRAM Red 8-bolt cranksets
  • STONE FC-RD004 cranksets

This chainring is compatible with both standard spindle and WIDE spindle SRAM road cranksets.


Bike Compatibility

Suitable for:

  • Road bikes
  • Folding bikes
  • Gravel bikes

Not recommended for mountain bike crankset conversions due to different offset and chainline requirements.


Specifications

ItemSpecification
BrandSTONE
ModelDMCRD-SR8-4OF-SL2
TypeRound narrow-wide single chainring
MountSRAM 8-bolt direct mount
Material7075-T651 aluminum
Thickness8mm
ProcessCNC machined
FinishAnodized
Offset4mm inward offset
Actual OffsetApprox. 4.4mm
Chainring Sizes38T, 40T, 42T, 44T, 46T, 48T, 50T, 52T, 54T, 56T, 58T
Tooth Profile OptionsAXS / Non-AXS
Installation ToolT20 Torx wrench
Recommended Torque4 Nm

Size and Weight Chart

TeethMax Outer DiameterWeightSKU
38T162 mm91.6 gDMCRD-SR8-4OF-SL2-38TY
40T169 mm100 gDMCRD-SR8-4OF-SL2-40TY
42T178 mm110.7 gDMCRD-SR8-4OF-SL2-42TY
44T186 mm119.5 gDMCRD-SR8-4OF-SL2-44TY
46T194 mm128 gDMCRD-SR8-4OF-SL2-46TY
48T202 mm136.4 gDMCRD-SR8-4OF-SL2-48TY
50T210 mm145 gDMCRD-SR8-4OF-SL2-50TY
52T219 mm150 gDMCRD-SR8-4OF-SL2-52TY
54T226 mm158.8 gDMCRD-SR8-4OF-SL2-54TY
56T235 mm172.6 gDMCRD-SR8-4OF-SL2-56TY
58T242 mm177.8 gDMCRD-SR8-4OF-SL2-58TY

Weights are for reference only. Product weight may vary slightly due to production updates or finishing differences.


Color Options

Available colors:

  • Anodized Black
  • Anodized Silver
  • Orange
  • Red
  • Grass Green
  • Purple
  • Sky Blue
  • Teal Green
  • Royal Blue
  • Rose Pink
  • Pink Blue Gradient

Actual product color may vary slightly from photos due to lighting and screen settings.


Recommended Tooth Sizes

Road Bike

  • Climbing: 38T / 40T
  • Daily riding: 46T / 48T / 50T
  • Racing: 52T / 54T

Folding Bike

  • Recommended: 50T / 52T / 54T

Gravel Bike

  • Recommended: 40T / 42T / 44T

Recommended sizes are for reference only. Please choose based on your drivetrain setup, cassette range, terrain, and riding style.


Installation Notes

  • Please confirm your crankset is SRAM road 8-bolt direct mount before purchase.
  • Install using a T20 Torx wrench.
  • Recommended installation torque: 4 Nm.
  • The chainring can be installed in any direction due to the round design.
  • This product is designed for road, folding bike, and gravel use.
  • Not recommended for MTB crankset conversion.
  • Choose the correct tooth profile according to your chain type:
    • AXS for SRAM FlatTop / AXS / T-Type chains
    • Non-AXS for standard non-FlatTop chains

Quality and Design

Each STONE chainring is made from premium 7075-T651 aluminum, a material known for its high strength, hardness, and excellent fatigue resistance. The CNC-machined structure improves accuracy and stiffness, while the anodized surface treatment helps resist corrosion and wear.

The reinforced tooth edge and multi-spoke round structure are designed to reduce deformation under load and deliver stable power transfer during hard efforts.

 

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

 

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

STONE SRAM 8-Bolt Direct Mount Round Narrow Wide Chainring hollow 38T–58T, 4mm Offset, AXS / Non-AXS Tooth Profile flattop

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