The Zenoah 36mm bore 4-bolt cylinder.
Race Porting offered, HT.
Championship Porting offered, HT or HR.
1mm stroked crank fits right in stock engine with no changes.
2mm stroked kit available with the head modifications, (a 30.5cc).
Reed Case poring offered, one or two boost ports added.
HP; 6.25 to 7.2, (about as good as it gets with Zenoah RC cylinders on gas).`
(Champ Ported “HT” and 2mm stroked 30.5cc 4-bolt engine, 6.5HP)
(Champ ported HT, stock or 1mm cranks can be used but prefer the 1mm crank, 6.5HP)
(Champ ported HR, stock or 1mm cranks can be used, but prefer the 1mm crank, 6.75 HP)
(2mm stroked 30.5cc top end kits, not ported. One kit sold with out the 2mm crank, and one kit sold with the 2mm crank, 4.8 HP)
(New Generation 30.5cc Champ Port HT top end kit, uses .005” copper cylinder base gasket, must be sealed, 6.5 HP)
(same kit as above but with 2mm crank, 6.5 HP)
(Champ ported HR new generation with the .005” copper base gasket used with the 2mm crank, 30.5cc, 6.75 HP)
(6 port reed case top end kits. Champ Ported HT or HR, used with stock stroke or 1mm cranks, 1mm preferred, 7 to 7.25 HP)
(6 port reed case top end kits. Champ Ported HT or HR, used with a 2mm crank, 30.5cc, 7.25 HP)