About all we can do, is give the clearances for the Honda engine series it was most likely copied from.
That's the 120-160cc OHV vertical shaft models.
For the GXV120/GXV140/GXV160 series, these are Intake 0.13-0.17mm [0.005-0.007"]; Exhaust 0.18-0.22mm [0.007-0.009"].
Both at TDC on compression stroke.
These are US market specs, but should be close enough.
Cheers,
Gadge
"ODK Mods can explain it to you, but they can't understand it for you..."
"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."
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