Should the GSX250 use 92 or 95 octane fuel?

[VonLincoln]

According to the official vehicle manual recommendation, the GSX250 should use 92 octane gasoline. In addition to checking the appropriate gasoline grade in the vehicle manual, the GSX250 can also be checked on the fuel tank cap, which will also be indicated. Usually, the fuel grade can also be determined based on the engine's compression ratio. Vehicles with an engine compression ratio between 8.6-9.9 should choose 92 octane gasoline, while those with a compression ratio between 10.0-11.5 should choose 95 octane gasoline. However, with the use of some new technologies, the gasoline grade cannot be determined solely by the compression ratio. A high compression ratio can also be tuned to use lower-grade gasoline. This is because, besides the compression ratio, other factors such as ignition timing, turbocharging technology, and Atkinson cycle technology also play a role. Generally, the higher the gasoline grade, the higher the octane number and the better the anti-knock performance. 92 octane gasoline contains 92% isooctane and 8% n-heptane, while 95 octane gasoline contains 95% isooctane and 5% n-heptane. If the GSX250 occasionally uses the wrong gasoline grade, simply switch back to the correct grade after use. However, long-term use of the wrong gasoline grade can have the following effects: For vehicles recommended for lower-grade gasoline, using higher-grade gasoline will not cause damage, but the increase in octane number will change the fuel's ignition point, leading to delayed combustion in the engine. This means the engine's power output and thermal efficiency will decrease, and the actual feedback experience is reduced performance. For vehicles recommended for higher-grade gasoline, using lower-grade gasoline can cause engine knocking. Because the octane number is too low, the gasoline's ignition point decreases, causing it to ignite prematurely during the compression stroke. If combustion occurs before the spark plug ignites during the compression stroke, resistance will occur during the upward stroke. This resistance will make the engine run very unstable. If the knocking is imperceptible, it only increases noise and does not significantly damage the engine. However, if there is noticeable knocking, it indicates the engine's condition is very severe. The vibration not only affects driving stability but can also cause abnormal wear on the pistons and cylinders, and in severe cases, cylinder scoring.