How much compression should a 85 kx250 have?

For a 1985 KX250, the recommended compression ratio is typically around 8.5:1 to 9.5:1. To achieve optimal performance, the engine should have a compression pressure of approximately 150-180 psi when tested with a compression gauge. It's essential to ensure that the engine is in good condition and has proper maintenance to achieve these compression values. If the compression is significantly lower, it may indicate wear or damage that needs to be addressed.