If your decompressor is working, 115 psi is normal. Honda specifies 85 to 121 psi. Hondas can be very tired and still show normal compression pressures.

Is the PCV disk (see brown disk in yellow circle, in the picture below) in good condition? Be sure it is not stuck either open or closed, and it is not worn right through in the center:

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If the disk valve is working properly, it sounds as if you may have to check the piston ring gaps.