Pressure Relief Valves

Was tearing down the bike and noticed that the PRV screen is about 60% covered in silvery melt. I am sure this is not good but out of curiosity, what happens if they get blocked up/restricted?


Thanks

B-Stone

I think oil comes out only when the pressure gets really excessive, in other words, never.

Jean

Jeandr said:

I think oil comes out only when the pressure gets really excessive, in other words, never.

Jean

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I'm not too certain about that. I fired up a fresh engine with a gauge attached at the rocker spindle. I had oil pressure way in excess of 100 psi . The relief valve was stuck. I cleaned it up and shimmed it for 60 psi. I realize this is with cold oil. Hot oil gives me about 10 psi per 1000 rpm, so I doubt the relief valve ever opens once the oil is hot, but when cold it certainly does, on my Combat anyway.