PhatheadRacing
Kawasaki KX100 Phathead cylinder head kit for HotRods stroker crank 1991-2021
Kawasaki KX100 Phathead cylinder head kit for Hotrods stroker crank 1991-2021
Our head kit is cut to be a direct bolt on fit to the stock KX100 cylinder with the HotRods +2mm and also cranks incorrectly marked as +4mm. Crank part numbers from HotRods are 4166(2006-2021) and 4116 (1991-2005). We do not suggest using the HotRods 4519 crankshaft with the nylon inserts. We also suggest the dual ring piston for the 2014+ KX100
+2mm 9.6cc chamber
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 stronger and transfers heat better than cast aluminum. The two piece design allows an increase in coolant flow as well as surface area which improves cooling for better consistency and performance.
The O-ring design eliminates the need to use a gasket. You can swap chambers without the cost of replacing gaskets.