For Crews and Equipment chainsaws, what is the minimum octane recommended?

• A. A minimum of 91 Octane
• B. 89 Octane
• C. 93 Octane
• D. 87 Octane

Answer: (A)

Octane rating measures a fuel’s resistance to knocking or pre-ignition in a spark-ignited engine. A chainsaw’s two-stroke engine operates under load and high compression, so using fuel that resists detonation helps prevent engine knocking, preserves power, and protects engine components. For Crews and Equipment chainsaws, the minimum octane recommended is 91. That means fuels at 91 octane or higher are acceptable and will meet the requirement; 93 octane would also be fine, but it isn’t the minimum. Using lower octane fuels (such as 89 or 87) is below the recommended minimum and can increase the risk of knocking and performance problems under heavy use.