The Zenoah 36mm bore. Cranks; stock, 1mm and 2mm.
Championship porting available, HR. (includes HR light weight Piston).
Reed Case porting available, 2 boost ports added, (new porting and compression for 2018, and running very very well, the best ESP has put out yet)
HP 6.50 to 6.75 for piston port engine (depending on crank choice)
HP; 7.25 plus for the new reed case top end kit.