Question about 1987 Yamaha SDR

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Bravo 250 I have an old 86 bravo engine that i am going to try to mount in an 85 citation, The rings are good but one side of the piston is scored fairly deep, what could be causing only one side to score? i want to fix the motor on the bench b4 it goes in the sled

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Can be from seizing due to overheat or lack of oil...
best replace the piston and rings

Posted on Nov 01, 2009

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What is the compression readings for a 1979 c10 i6 250


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