Malossi 94cc Piston Kit - 52mm BoreTECH: (Most Euro Kits)50cc = 40mm Piston Bore x 39.2mm Stroke70cc = 47.6mm Piston Bore x 39.2mm Stroke86cc = 50mm Piston Bore x 44mm Stroke90cc = 50mm Piston bore x 45.8mm Bore94cc = 52mm Piston Bore x 44mm Stroke