Mine has 1 ring per piston, But, the ring for the GT80, part #ZEN8488C41200, that I ordered from Horizon, is to LARGE. Putting the Ring in the cylinder by itself, the ends overlap. I do not have anything small enough to measure inside the cylinder. However, the piston mics approx. 39mm, But, it only has 1 ring.
I would re-use the old rings but one snapped as I was removing them.
Looks like I have opened a can of worms. LOL
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