Iame x30 actual piston size versus bore size on box

So I know Iame x30 replacement piston set are labelled on box with actual bore size not piston size.

What is actual piston size? I have seen to different set of descriptions online one with .08mm difference and one .11mm difference.

I took notes last time I ordered a 54.0 V or green replacement piston but I cant find my notes anywhere.

Let me know thanks.

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I have some ideas, but don’t want to assume. @Ryon_Beachner, what’s the skinny on X30 pistons?

@Jamie_Gonzalez this is directly from IAME USA East website under the tech documents.

"Play between piston and liner must be
0.11 ÷ 0.12mm. If play is higher than 0.14mm replace piston.

Pistons are measured at 17.5mm from bottom.

Size of liner to be matched with piston is marked on
top of piston with a green or red dot or with letter V or

If the size on piston top is marked with:

-a green dot or letter V: add 0.01mm to size marked
on the piston to match the liner size.

-a red dot or letter R: add 0.02 mm to size
marked on the piston to match the liner size."

I hope this helps. Attached is the link to the overhaul manual directly from IAME.


Not exactly what I am looking for.

What I am trying to confirm is the piston size.

For example if I purchase a 54.0v is the piston in the box 53.92 or 53.89?

I found some info online that indicates replacement piston are .08 smaller than box size/piston top and another states .11