Tomos A35 38mm Std piston kit

Factory pistons with windows have not produced since 2007. Tomos development, at that time, found (tested and measured) that the windows have no effect. Tested on a sustainable test and on a bench test! Since then, pistons 227686 (PN-102 vertex factory piston) has no windows. The original factory piston manufacturer (MOTINS) collapsed in 2008. All pistons with windows that are now appearing on the market are aftermarket copies of MOTIS piston. ( DMP version- WE ALSO HAVE AVAILABLE) . Vertex is the highest quality manufacturer of pistons for replacement on TOMOS mopeds and is the current OEM manufacture.