The e*thirteen Helix R 107BCD Chainring, designed for 4-bolt 107BCD cranks like SRAM Red or Force including power meter equipped cranks, offers a performance upgrade for Gravel and Road cyclists. The 38, 40, and 42 tooth rings pair perfectly with e*thirteens cassettes for more overall range and higher top speeds. Made from durable premium 7075 alloy, they’re CNC sculpted for a high stiffness-to-weight ratio. Compatible with both SRAM and Shimano 11 and 12-speed drivetrains. Chainline is set by SRAM Crank assembly.

• Compatible with 4-bolt 107 BCD SRAM cranks and Quarq power meter cranks
• M4 narrow-wide tooth profile provides Shimano and SRAM 11/12-speed chain compatibility (Including flattop chains)
• excellent chain retention
• and reduced wear
• 4.8mm offset (Chainline is determined by SRAM Crank assembly
• 45mm for normal width cranks
• 47.5mm for wide cranks)
• Forged from premium 7075-T7 aluminum
• then extensively CNC optimized for light weight
• and technical aesthetics
• Durable 7075-T7 construction for long wear-life
• stiffness
• and strength
• Ring Position/Type: Chain Retaining Single Ring
• Tooth Count: 42
• Drivetrain Speeds: 11
• Drivetrain Speeds: 12
• Round or Oval: Round
• Chainring BCD: 107
• Material: Aluminum
• Color: Black
• Weight: 81
• Defined Color: Black