Yamaha YZ85 YZ80 Phathead cylinder head kit 1993-2018 YZ250 Use the NGK MR8BI or

Use the NGK MR8BI or OE 2024+ spark plug

Yamaha YZ65 2018-2025+ Phathead cylinder head kit

Honda CR250 Phathead cylinder head kit 2005-2007

4cc 105+ octane

Yamaha YZ85 YZ80 Phathead cylinder head kit 1993-2018 YZ250 Use the NGK MR8BI orYamaha YZ85 Phathead cylinder head kit 1993 2018 YZ80 Chamber selection: Y01 6. 4cc StockY02 6. 0cc (95+ octane)Y03 5. 6cc (100+ octane)Y04 5. 2cc (105+ octane) 52. 5mm big bore chamber 100+ octane for use with big bore piston 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