What Engine Sizes Does the Chain Tensioner Fit?

The Duluth Cycle Advanced 2-Stroke Motorized Bicycle Chain Tensioner is designed to fit all 2-stroke motorized bicycle engines, including:

  • 49cc engines
  • 66cc engines
  • 80cc engines

Key Compatibility Features

Our CNC-machined tensioner includes countersunk mounting holes, which means your pedals will never scrape or have clearance issues during installation. This universal design works with the vast majority of 2-stroke motorized bicycle engine kits on the market.

What Makes Our Tensioner Different

Unlike standard tensioners that come with engine kits, our advanced spring-loaded design:

  • Automatically maintains proper chain tension
  • Reduces chain noise and vibration
  • Prevents chain derailment
  • Works with standard #415 motorized bicycle chain

Before You Order

While our tensioner fits 49cc, 66cc, and 80cc 2-stroke engines, we recommend verifying your bike has adequate frame clearance. Most standard bicycle frames accommodate our tensioner without issues.

Jan 13, 2026

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