AZQP / Cylinder Works / Hotrods Complete Top End Rebuild Kit! This is the best and most reliable rebuild kit on the market! Fits Yamaha YZ250 2 Stroke Dirt Bikes. Years 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022. This Complete Rebuild Kit Includes. Cylinder Works 66.40mm Stock Bore Nikasil Plated Cylinder. Vertex Forged & Coated Piston Kit (Includes, Piston, Pin, Rings & Clips) (Perfect For Pump Gas). Complete Top End Gasket Set. Hotrods Heavy Duty Wrist Pin Bearing. Cylinder Works Cylinder Head.