for Vespa 90-125/PV/ET3/PK/S/XL/2 57,5 mm long thread squish band 1,0 mm 13,5:1 incl. O-ring TUNING SPORT – high-performance Product description The MALOSSI 136cc Cylinder Head is the basis on which MMW and Worb5 both work to fit the POLINI 130cc. MMW updated this cylinder head to fit modern needs. The angle and width of the squish band clearance are modified, the spherical shape of every cylinder combustion area is optimised, the layout for these heads is made of many individually constructed items for ESC pilots. The feedback from many scooter pilots is collected and used. The heads are made for the MALOSSI 136cc, The POLINI 130cc and for GS pistons 130cc to be used in MALOSSI/POLINI/DR 130-136cc cylinders. Higher performance, less pinking, increased durability. These are the positive results of these head tunings. POLINI 130cc profits especially, because the original head often leaks. Also, the W5 takes the 136cc as basis. Here also is a version for the POLINI 130cc