Specifically developed for reliable single-speed and BMX drivetrains.

The ACS Maindrive Freewheel in 1/8″ 18T is engineered for durability and consistent performance. Utilizing ACS’s robust “Maindrive” system, it delivers a positive engagement for confident power transfer, making it a trusted choice for various applications from urban commuting to BMX riding.

• Designed for 1/8″ chains, common in single-speed and BMX setups.
• 18-tooth count provides a versatile gear ratio for a balance of speed and climbing ability.
• Features ACS’s renowned strong engagement and long-lasting construction.
• Compatible with standard freewheel hubs.