I received 2 new oversized pistons 0.5 ( nsr250 ProX ) from japan with only 1 ring on each. My engineer told me that the sleeves cannot be done by him but a special drilling process after needed plating to be done. PLEASE explain why?!?(plating)

This is what I was trying to explain a couple days ago. The cylinders are Nikasil plated. Its sort of like chrome plating but its not. Its a different process with different properties. Then the cylinder has to be honed with a special diamond hone. There is only a few places that can do it. Cost is about $125-$150 per cylinder.
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james
Its not how fast you go...Its how you go fast.
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http://members.rennlist.com/j911brick/rennlist3_002.htm

You never need oversize rings for normal maintenace. The cylinder is repaired if damaged, then replated and honed to the same specs as new, so the pistons are allways the same size.

One ring pistons are used in the RS250 and can be used in NSR with some disadvantages, that are probably described here on the board somewhere
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Poul
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