How to machine 2 Stroke cases to accept big bore sleeves. Boring CASES Yamaha, Kawasaki, 62t 701 23 March 2020 In this video i show you how to bore engine cases to accept larger sleeves. This was a set of Yamaha 61x cases BUT this can method can be used on any 2 or 4 stroke engine with a removable cylinder. Comments There are no comments yet. Leave message Your rating: Your review: Share Tweet