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Plan on inspecting a used 570 today that has 1200 miles / 122 hours.

Anyone have an idea of what I should expect when doing a compression check?

Seems 130 psi is the desired norm based on several other models in the 500cc range, but being used I don't expect it to be quite that high.

Is there a range that will help me make a decision as to whether or not the reading I get seems relatable to the miles and hours put on the machine?

For example is 100 psi way too low, yet 120 could be expected and should indicate that the top end is still in pretty good condition?

Thanks for any input
 

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120 to 150 (throttle held wide open at least 5 compression strokes) is what I expect to see - below 120 is marginal - below 100 is bad, bur might just indicate a valve adjustment is needed. This where the difference between a cold check and a hot check can be beneficial. If the compression comes up when hot, it's usually the valves - if it drops it's usually the rings. Above 150 it needs 95 or higher octane fuel, but it depends on the engine design. Check the compression on a push lawn mower for example.
 
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