New old stock Yamaha KT100 Y-4 cylinder, part # 787-11311-02 . Includes new 52.05mm piston and new O&H Gold 52.10mm ring. Piston bearing, pin & pin clips are not included.

The box is marked "407 Blowdown" which is likely accurate but I have not verified personally.

Please note this is a brand new cylinder, so the bore needs to be matched to the piston size prior to use.

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