Honda CR250 2005-2007 Phathead cylinder head kit cobra 6cc (110+ octane)

6cc (110+ octane)

AY21 - 21cc  (95+ octane)

Yamaha YZ85 Phathead cylinder head kit 2019-2026

4cc Stock compression

WR250F WR426F YFM250 Bear Tracker YFM350F Wolverine 4x4 YFM350X Warrior YFM400 Big Bear 2x4 YFM400 Big Bear 4x4 YFM400A Kodiak YFM400F Kodiak 4x4 YFM600FW Grizzly 4x4 YFM660R Raptor YFS200 Blaster 2000

Honda CR250 2005-2007 Phathead cylinder head kit cobra 6cc (110+ octane)Honda CR250 Phathead cylinder head kit 2005 2007 Chamber selection: H30 21. 8cc Stock H31 20. 6cc 95+ octane H32 19. 7cc 100+ octane H33 18. 5cc 105+ octane H34 17. 4cc 110+ octane Phathead Kits include a head shell with one combustion chamber, two sets of o rings, cylinder head nuts, copper washers, some stickers for your bike and tool box and installation instructions.. Phathead cylinder heads are made of 6061 T6 billet aluminum. The material is