If you use the parts guide on the left side of the website, you can get part number. An 88 NSR should be a 2J. Use the parts number on Fowlers website and it should show you the superceded part number. Most likely for an MC21. Send the pistons to the platers and they will adjust the cylinder coating to the pistons. You need to be sure that the exhaust bridge on the cylinders aren't damaged, otherwise they will probably fail and seize
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